Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating Activities:
Net income	$ 63,899	$ 33,871	$ 102,663	$ 56,120
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Stock-based compensation expense			6,075	2,038
Depreciation and amortization			9,952	2,704
Inventory impairments	200		750	4,850
Other-than-temporary impairment of marketable securities				182
Net gain on sale of available-for-sale marketable securities				(1,758)
Net gain on marketable equity securities	(1,278)		(125)
Amortization of discount / premiums on marketable debt securities, net			(366)
Deferred income tax expense			3,557	10,033
Net changes in assets and liabilities:
Trade and other receivables			(2,317)	5,419
Mortgage loans held-for-sale			30,929	43,491
Prepaid and other assets			(5,108)	(7,602)
Accounts payable and accrued liabilities			15,835	8,845
Net cash provided by (used in) operating activities			(56,188)	122,136
Investing Activities:
Purchases of marketable securities			(14,659)	(12,043)
Maturities of marketable securities			50,000
Sales of marketable securities			12,460	11,450
Purchases of property and equipment			(13,051)	(1,364)
Net cash provided by (used in) investing activities			34,750	(1,957)
Financing Activities:
Payments on mortgage repurchase facility, net			(31,521)	(45,358)
Dividend payments			(33,793)	(25,809)
Proceeds from exercise of stock options			5,835	7,304
Net cash used in financing activities			(59,479)	(63,863)
Net increase (decrease) in cash, cash equivalents and restricted cash			(80,917)	56,316
Cash, cash equivalents and restricted cash:
Beginning of period			514,240	286,687
End of period	433,323	343,003	433,323	343,003
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	433,323	343,003	433,323	343,003
End of period	433,323	343,003	433,323	343,003
Homebuilding Segment [Member]
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Inventory impairments	200		750	4,850
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	378,219	314,814	378,219	314,814
Restricted cash	7,443	5,027	7,443	5,027
Financial Services Segment [Member]
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	$ 47,661	$ 23,162	47,661	23,162
Housing Completed or Under Construction [Member]
Net changes in assets and liabilities:
Housing completed or under construction and land under development			(133,576)	(39,707)
Land and Land Under Development [Member]
Net changes in assets and liabilities:
Housing completed or under construction and land under development			$ (84,457)	$ 37,521