| 
           Operating and Reporting Segments (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|
| 
           Mar. 31, 2014 
         | 
        
           Mar. 31, 2013 
         | 
      |||||||
| Revenue | ||||||||
| Revenue | $ 408,345 | [1] | $ 336,435 | [1] | ||||
| Segment operating income | ||||||||
| Segment operating income | 44,943 | 24,779 | ||||||
| Financial Services Profit | 3,025 | 3,056 | ||||||
| Corporate and unallocated | (5,976) | [2] | (5,847) | [2] | ||||
| Loss from other unconsolidated entities, net | (169) | (155) | ||||||
| Interest expense | (2,713) | (5,128) | ||||||
| Other income, net | 648 | 470 | ||||||
| Loss on early extinguishment of debt | 0 | (700) | ||||||
| Earnings before income taxes | 39,758 | 16,475 | ||||||
| 
           West [Member] 
         | 
        ||||||||
| Revenue | ||||||||
| Revenue | 192,681 | 189,205 | ||||||
| Segment operating income | ||||||||
| Segment operating income | 24,810 | 19,163 | ||||||
| 
           Central [Member] 
         | 
        ||||||||
| Revenue | ||||||||
| Revenue | 119,715 | 90,789 | ||||||
| Segment operating income | ||||||||
| Segment operating income | 9,469 | 2,380 | ||||||
| 
           East [Member] 
         | 
        ||||||||
| Revenue | ||||||||
| Revenue | 95,949 | 56,441 | ||||||
| Segment operating income | ||||||||
| Segment operating income | $ 10,664 | $ 3,236 | ||||||
          
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