Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ 901,248	$ 878,539	$ 797,197
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	21,992	20,818	20,168
Equity-based compensation expense	50,794	78,532	75,701
Contract land deposit impairments (recoveries), net	28,079	(680)	11,760
Gain on sale of loans, net	(168,720)	(128,642)	(122,755)
Deferred tax (benefit) expense	(17,565)	(4,070)	914
Mortgage loans closed	(5,323,932)	(5,169,422)	(4,828,615)
Mortgage loans sold and principal payments on mortgage loans held for sale	5,536,568	5,260,600	4,845,999
Distribution of earnings from unconsolidated joint ventures	1,432	3,476	4,596
Net change in assets and liabilities:
Increase in inventory	(362,384)	(94,178)	(6,911)
Decrease (increase) in contract land deposits	519	(16,994)	(30,863)
(Increase) decrease in receivables	(1,675)	2,754	(1,008)
Increase (decrease) in accounts payable and accrued expenses	168,667	33,926	(30,713)
Increase (Decrease) in Contract with Customer, Liability	108,872	(6,360)	(11,787)
Other, net	(18,626)	8,236	(557)
Operating activities	925,269	866,535	723,126
Net cash provided by operating activities	925,269	866,535	723,126
Cash flows from investing activities:
Investments in and advances to unconsolidated joint ventures	(435)	(702)	(284)
Distribution of capital from unconsolidated joint ventures	11,625	8,247	10,515
Purchase of property, plant and equipment	(16,119)	(22,699)	(19,665)
Proceeds from the sale of property, plant and equipment	996	1,870	1,257
Net Cash Provided by (Used in) Investing Activities	(3,933)	(13,284)	(8,177)
Cash flows from financing activities:
Purchase of treasury stock	(371,078)	(698,417)	(846,134)
Proceeds from Issuance of Senior Long-term Debt	923,905	0	0
Payments of Debt Issuance Costs	(5,062)	0	0
Finance Lease, Principal Payments	(989)	(306)	0
Distributions to partner in consolidated variable interest entity	0	0	(234)
Proceeds from the exercise of stock options	180,866	274,028	174,110
Financing activities	727,642	(424,695)	(672,258)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	1,648,978	428,556	42,691
Financing activities	727,642	(424,695)	(672,258)
Cash, restricted cash, and cash equivalents, beginning of the year	1,160,804	732,248	689,557
Cash, restricted cash, and cash equivalents, end of the year	2,809,782	1,160,804	732,248
Supplemental disclosures of cash flow information:
Interest paid during the year, net of interest capitalized	36,805	24,453	24,178
Income taxes paid during the year, net of refunds	$ 163,076	$ 153,915	$ 181,166