Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash Flows From Operating Activities:
Net income	$ 274,966,000	$ 317,769,000
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
(Income) loss from unconsolidated joint ventures	(9,760,000)	(2,643,000)
Depreciation and amortization	41,818,000	43,193,000
Amortization of stock-based compensation	14,282,000	11,216,000
Deferred income tax provision	22,972,000	8,118,000
Other operating activities	7,062,000	100,000
Changes in cash and equivalents due to:
Mortgage loans held for sale	101,968,000	154,622,000
Inventories - owned	(450,620,000)	(366,095,000)
Inventories - not owned	(56,722,000)	(29,192,000)
Other assets	(12,206,000)	7,665,000
Accounts payable	(34,028,000)	13,122,000
Accrued liabilities	(23,207,000)	9,787,000
Net cash provided by (used in) operating activities	(123,475,000)	167,662,000
Cash Flows From Investing Activities:
Investments in unconsolidated homebuilding joint ventures	(33,212,000)	(27,000,000)
Distributions of capital from unconsolidated homebuilding joint ventures	12,770,000	23,727,000
Net cash paid for acquisitions	(44,477,000)
Other investing activities	(11,113,000)	(5,389,000)
Net cash provided by (used in) investing activities	(76,032,000)	(8,662,000)
Cash Flows From Financing Activities:
Change in restricted cash	(794,000)	7,309,000
Borrowings from revolving credit facility	685,550,000	1,008,000,000
Principal payments on revolving credit facility	(389,950,000)	(862,000,000)
Principal payments on secured project debt and other notes payable	(909,000)	(10,389,000)
Principal payment on senior notes payable	(483,000,000)	(280,000,000)
Proceeds from the issuance of senior notes payable	579,125,000	300,000,000
Payment of debt issuance costs	(5,019,000)	(2,657,000)
Net proceeds from (payments on) mortgage credit facility	(94,641,000)	(141,524,000)
Repurchases of common stock	(150,014,000)	(137,464,000)
Common stock dividend payments	(13,427,000)	(14,264,000)
Issuance of common stock under employee stock plans, net of tax withholdings	(5,807,000)	1,868,000
Other financing activities	(67,000)	(199,000)
Net cash provided by (used in) financing activities	121,047,000	(131,320,000)
Net increase (decrease) in cash and equivalents	(78,460,000)	27,680,000
Cash and equivalents at beginning of period	208,127,000	186,594,000
Cash and equivalents at end of period	129,667,000	214,274,000
Cash and equivalents at end of period	208,127,000	186,594,000
Homebuilding [Member]
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
(Income) loss from unconsolidated joint ventures	(9,760,000)	$ (2,643,000)
Cash Flows From Financing Activities:
Cash and equivalents at beginning of period	191,086,000
Cash and equivalents at end of period	83,310,000
Cash and equivalents at end of period	83,310,000
Financial Services [Member]
Cash Flows From Financing Activities:
Cash and equivalents at beginning of period	17,041,000
Cash and equivalents at end of period	46,357,000
Cash and equivalents at end of period	$ 46,357,000