Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Details)

v2.4.1.9
Stockholders' Equity (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Jan. 31, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]        
Balance, shares 39,147,153us-gaap_CommonStockSharesIssued     2,530,000us-gaap_CommonStockSharesIssued
Balance $ 1,109,489us-gaap_StockholdersEquity $ 841,392us-gaap_StockholdersEquity    
Net earnings 16,400us-gaap_NetIncomeLoss 25,377us-gaap_NetIncomeLoss    
Exercise/vesting of equity awards, value 2,834us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation 707us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation    
Excess income tax benefit from stock-based awards 1,935us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation 2,275us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation    
Equity award compensation expense 4,630us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue 2,411us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue    
Issuance of stock, value   110,432us-gaap_StockIssuedDuringPeriodValueNewIssues [1]    
Balance, shares 39,616,663us-gaap_CommonStockSharesIssued     2,530,000us-gaap_CommonStockSharesIssued
Balance 1,135,288us-gaap_StockholdersEquity 982,594us-gaap_StockholdersEquity    
Common stock, shares issued 39,616,663us-gaap_CommonStockSharesIssued     2,530,000us-gaap_CommonStockSharesIssued
Common stock, par value (in dollars per share) $ 0.01us-gaap_CommonStockParOrStatedValuePerShare   $ 0.01us-gaap_CommonStockParOrStatedValuePerShare $ 0.01us-gaap_CommonStockParOrStatedValuePerShare
Sale of stock, price per share (in dollars per share)       $ 45.75us-gaap_SaleOfStockPricePerShare
Common Stock [Member]        
Increase (Decrease) in Stockholders' Equity [Roll Forward]        
Balance, shares 39,147,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
36,244,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Balance 391us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
362us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Exercise/vesting of equity awards, shares 470,000us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
340,000us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Exercise/vesting of equity awards, value 5us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
4us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Issuance of stock, shares   2,530,000us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
[1]    
Issuance of stock, value   25us-gaap_StockIssuedDuringPeriodValueNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
[1]    
Balance, shares 39,617,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
39,114,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Balance 396us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
391us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Common stock, shares issued 39,617,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
39,114,000us-gaap_CommonStockSharesIssued
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Additional Paid-in Capital [Member]        
Increase (Decrease) in Stockholders' Equity [Roll Forward]        
Balance 538,788us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
412,961us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
   
Exercise/vesting of equity awards, value 2,829us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
703us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
   
Excess income tax benefit from stock-based awards 1,935us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
2,275us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
   
Equity award compensation expense 4,630us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
2,411us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
   
Issuance of stock, value   110,407us-gaap_StockIssuedDuringPeriodValueNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
[1]    
Balance 548,182us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
528,757us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AdditionalPaidInCapitalMember
   
Retained Earnings [Member]        
Increase (Decrease) in Stockholders' Equity [Roll Forward]        
Balance 570,310us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
428,069us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
   
Net earnings 16,400us-gaap_NetIncomeLoss
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
25,377us-gaap_NetIncomeLoss
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
   
Balance $ 586,710us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
$ 453,446us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_RetainedEarningsMember
   
[1] In January 2014, we issued 2,530,000 shares of common stock in a secondary public offering, par value $0.01 per share, at a price of $45.75 per share.