CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Common Stock [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Other Comprehensive Income [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Treasury Stock [Member]	Treasury Stock [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Noncontrolling Interests [Member]	Noncontrolling Interests [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance at Dec. 31, 2017	$ 6,547		$ 802,961		$ (32,405)		$ 2,646,937		$ (313,220)		$ 3,403		$ 3,114,223
Beginning balance (ASU 2014-09 [Member]) at Dec. 31, 2017		$ 0		$ 0		$ 0		$ (9,722)		$ 0		$ 0		$ (9,722)
Beginning balance (ASU 2018-02 [Member]) at Dec. 31, 2017		$ 0		$ 0		$ 0		$ 7,925		$ 0		$ 0		$ 7,925
Beginning balance (in shares) at Dec. 31, 2017	65,472								(5,783)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises	$ 0		2,161		0		0		$ 11,151		0		13,312
Stock option exercises (in shares)	0								232
Issuance of stock for equity awards, net of forfeitures	$ 0		(879)		0		0		$ 879		0		0
Issuance of stock for equity awards, net of forfeitures (in shares)	0								15
Tax withholdings on equity award vesting	$ 0		0		0		0		$ (4,822)		0		(4,822)
Tax withholdings on equity award vesting (in shares)	0								(61)
Treasury stock purchases	$ 0		0		0		0		$ (776)		0		(776)
Treasury stock purchases (in shares)	0								(11)
Amortization of unearned share-based compensation	$ 0		19,104		0		0		$ 0		0		19,104
Total comprehensive income (loss), net of taxes	0		0		(1,106)		78,452		0		626		77,972
Return of investment to noncontrolling interests	0		0		0		0		0		(915)		(915)
Ending balance at Dec. 31, 2018	$ 6,547		823,347		(33,511)		2,723,592		$ (306,788)		3,114		3,216,301
Ending balance (in shares) at Dec. 31, 2018	65,472								(5,608)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises	$ 0		675		0		0		$ 5,121		0		5,796
Stock option exercises (in shares)	0								93
Issuance of stock for equity awards, net of forfeitures	$ 0		(1,735)		0		0		$ 1,735		0		0
Issuance of stock for equity awards, net of forfeitures (in shares)	0								32
Tax withholdings on equity award vesting	$ 0		0		0		0		$ (2,031)		0		(2,031)
Tax withholdings on equity award vesting (in shares)	0								(30)
Amortization of unearned share-based compensation	$ 0		13,612		0		0		$ 0		0		13,612
Total comprehensive income (loss), net of taxes	0		0		(4,288)		142,347		0		672		138,731
Return of investment to noncontrolling interests	0		0		0		0		0		(817)		(817)
Ending balance at Dec. 31, 2019	$ 6,547		835,899		(37,799)		2,865,939		$ (301,963)		2,969		3,371,592
Ending balance (in shares) at Dec. 31, 2019	65,472								(5,513)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises	$ 0		26		0		0		$ 327		0		353
Stock option exercises (in shares)	0								15
Issuance of stock for equity awards, net of forfeitures	$ 0		(5,668)		0		0		$ 5,668		0		0
Issuance of stock for equity awards, net of forfeitures (in shares)	0								103
Tax withholdings on equity award vesting	$ 0		0		0		0		$ (3,193)		0		(3,193)
Tax withholdings on equity award vesting (in shares)	0								(39)
Amortization of unearned share-based compensation	$ 0		14,722		0		0		$ 0		0		14,722
Total comprehensive income (loss), net of taxes	0		0		(23,653)		(272,546)		0		954		(295,245)
Return of investment to noncontrolling interests	0		0		0		0		0		(676)		(676)
Ending balance at Dec. 31, 2020	$ 6,547		$ 844,979		$ (61,452)		$ 2,593,393		$ (299,161)		$ 3,247		$ 3,087,553
Ending balance (in shares) at Dec. 31, 2020	65,472								(5,434)