| 
           Operating and Reporting Segments (Details) (USD $) 
        In Thousands, unless otherwise specified  | 
        3 Months Ended | 9 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 
           Sep. 30, 2013 
         | 
        
           Sep. 30, 2012 
         | 
        
           Sep. 30, 2013 
         | 
        
           Sep. 30, 2012 
         | 
      |||||||||
| Revenue | ||||||||||||
| Revenue | $ 492,080 | [1] | $ 342,643 | [1] | $ 1,278,465 | [1] | $ 829,088 | [1] | ||||
| Segment operating income | ||||||||||||
| Segment operating income | 63,965 | 24,683 | 137,667 | 48,063 | ||||||||
| Financial Services Profit | 4,294 | 2,985 | 11,515 | 6,743 | ||||||||
| Corporate and unallocated | (8,662) | [2] | (7,323) | [2] | (22,011) | [2] | (17,233) | [2] | ||||
| Earnings from Other Unconsolidated Entities Net | 46 | (74) | (229) | (348) | ||||||||
| Interest expense | (3,462) | (5,009) | (13,113) | (18,718) | ||||||||
| Other (expense)/income, net | 605 | (8,276) | 1,760 | (7,481) | ||||||||
| Loss on extinguishment of debt | 0 | 0 | (3,796) | (5,772) | ||||||||
| Earnings/(loss) before income taxes | 56,786 | 6,986 | 111,793 | 5,254 | ||||||||
| 
           West [Member] 
         | 
        ||||||||||||
| Revenue | ||||||||||||
| Revenue | 259,669 | 186,507 | 695,615 | 415,471 | ||||||||
| Segment operating income | ||||||||||||
| Segment operating income | 41,298 | 15,319 | 95,356 | 26,970 | ||||||||
| 
           Central [Member] 
         | 
        ||||||||||||
| Revenue | ||||||||||||
| Revenue | 139,307 | 104,526 | 357,406 | 279,004 | ||||||||
| Segment operating income | ||||||||||||
| Segment operating income | 12,677 | 5,673 | 22,320 | 11,325 | ||||||||
| 
           East [Member] 
         | 
        ||||||||||||
| Revenue | ||||||||||||
| Revenue | 93,104 | 51,610 | 225,444 | 134,613 | ||||||||
| Segment operating income | ||||||||||||
| Segment operating income | $ 9,990 | $ 3,691 | $ 19,991 | $ 9,768 | ||||||||
          
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