Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 797,197	$ 537,521	$ 425,262
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	20,168	22,667	22,269
Equity-based compensation expense	75,701	44,562	43,598
Contract land deposit impairments (recoveries), net	11,760	1,238	(4,269)
Gain on sale of loans, net	(122,755)	(99,132)	(85,535)
Deferred tax expense (benefit)	914	61,290	(10,024)
Mortgage loans closed	(4,828,615)	(4,077,372)	(3,660,269)
Mortgage loans sold and principal payments on mortgage loans held for sale	4,845,999	4,182,220	3,710,250
Distribution of earnings from unconsolidated joint ventures	4,596	4,788	10,016
Net change in assets and liabilities:
Increase in inventory	(6,911)	(154,099)	(85,194)
Decrease (increase) in contract land deposits	(30,863)	8,177	(32,280)
Increase in receivables	(1,008)	(348)	(8,779)
Increase in accounts payable and accrued expenses	(30,713)	10,789	58,532
Increase in customer deposits	(11,787)	27,797	11,271
Other, net	(557)	256	(1,860)
Net cash provided by operating activities	723,126	570,354	392,988
Cash flows from investing activities:
Investments in and advances to unconsolidated joint ventures	(284)	(3,800)	(653)
Distribution of capital from unconsolidated joint ventures	10,515	8,029	11,672
Purchase of property, plant and equipment	(19,665)	(20,269)	(22,369)
Proceeds from the sale of property, plant and equipment	1,257	847	1,000
Net cash used in investing activities	(8,177)	(15,193)	(10,350)
Cash flows from financing activities:
Purchase of treasury stock	(846,134)	(422,166)	(455,351)
Distributions to partner in consolidated variable interest entity	(234)	0	(150)
Proceeds from the exercise of stock options	174,110	140,525	38,106
Net cash used in financing activities	(672,258)	(281,641)	(417,395)
Net increase (decrease) in cash and cash equivalents	42,691	273,520	(34,757)
Cash and cash equivalents, beginning of the year	689,557	416,037	450,794
Cash and cash equivalents, end of the year	732,248	689,557	416,037
Supplemental disclosures of cash flow information:
Interest paid during the year, net of interest capitalized	24,178	23,251	20,922
Income taxes paid during the year, net of refunds	$ 181,166	$ 260,232	$ 218,984