Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Statement of Cash Flows [Abstract]
Finance Lease, Principal Payments	$ (12)	$ 0
Cash flows from operating activities:
Net income	398,615	369,223
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,146	10,024
Equity-based compensation expense	37,910	28,104
Contract land deposit and other (recoveries) impairments, net	(23)	44
Gain on sale of loans, net	(67,919)	(58,891)
Mortgage loans closed	(2,373,748)	(2,223,302)
Mortgage loans sold and principal payments on mortgage loans held for sale	2,428,410	2,229,894
Distribution of earnings from unconsolidated joint ventures	2,156	2,849
Net change in assets and liabilities:
Increase in inventory	(144,618)	(187,416)
(Increase) decrease in contract land deposits	(13,554)	9,333
Increase in receivables	(9,597)	(10,417)
Increase (decrease) in accounts payable and accrued expenses	32,771	(11,332)
Increase in customer deposits	7,961	22,000
Other, net	(5,891)	(10,663)
Net cash provided by operating activities	302,619	169,450
Cash flows from investing activities:
Investments in and advances to unconsolidated joint ventures	(335)	(284)
Distribution of capital from unconsolidated joint ventures	7,167	6,027
Purchase of property, plant and equipment	(10,699)	(9,251)
Proceeds from the sale of property, plant and equipment	1,069	425
Net cash used in investing activities	(2,798)	(3,083)
Cash flows from financing activities:
Purchase of treasury stock	(304,479)	(483,538)
Proceeds from the exercise of stock options	178,831	86,094
Net cash used in financing activities	(125,660)	(397,444)
Net increase (decrease) in cash, restricted cash, and cash equivalents	174,161	(231,077)
Cash, restricted cash, and cash equivalents, beginning of the period	732,248	689,557
Cash, restricted cash, and cash equivalents, end of the period	906,409	458,480
Supplemental disclosures of cash flow information:
Interest paid during the period, net of interest capitalized	12,052	12,151
Income taxes paid during the period, net of refunds	$ 71,486	$ 86,269