Quarterly Results (unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011 Contract Settlement Backlog	Sep. 30, 2011 Settlement Backlog Contract	Jun. 30, 2011 Backlog Contract Settlement	Mar. 31, 2011 Contract Settlement Backlog	Dec. 31, 2010 Backlog Contract Settlement	Sep. 30, 2010 Backlog Settlement Contract	Jun. 30, 2010 Backlog Contract Settlement	Mar. 31, 2010 Backlog Settlement Contract	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Financial Data and Operating Information on a Quarterly Basis
Mortgage banking fees									$ 47,954	$ 61,134	$ 60,381
Net income	32,392	43,409	38,445	15,174	58,698	43,944	71,276	32,087	129,420	206,005	192,180
Diluted earnings per share	$ 6.32	$ 7.98	$ 6.48	$ 2.52	$ 9.96	$ 7.31	$ 11.13	$ 5.01	$ 23.01	$ 33.42	$ 31.26
Contracts for sale, net of cancellations (units)	2,158	2,218	2,468	2,403	1,765	2,151	2,559	2,940
Settlements (units)	2,391	2,255	2,207	1,634	2,639	2,127	3,345	1,919
Backlog, end of period (units)	3,676	3,909	3,946	3,685	2,916	3,790	3,766	4,552
Loans closed	520,919	489,866	504,116	353,571	597,949	497,404	706,551	418,042
Homebuilding:
Financial Data and Operating Information on a Quarterly Basis
Revenues	728,808	696,980	682,663	502,744	794,470	661,935	946,972	577,381	2,611,195	2,980,758	2,683,467
Gross profit-homebuilding operations	112,086	124,598	124,062	84,824	139,505	121,152	175,497	106,312
Mortgage Banking:
Financial Data and Operating Information on a Quarterly Basis
Mortgage banking fees	$ 12,480	$ 10,496	$ 13,218	$ 11,760	$ 16,535	$ 14,234	$ 17,532	$ 12,833	$ 47,954	$ 61,134	$ 60,381