CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]
Common stock, issued		103,988,707				36,270,015
Additional paid-in capital			$ 769,411
Retained earnings				$ 1,458,330
Accumulated other comprehensive income					$ (5,288)
Total stockholders’ equity	$ 466,353	$ 10,399				$ (1,766,499)
Net income	32,711			32,711
Total other comprehensive (loss) income	4,153				4,153
Issuance of shares of common stock (in shares)		12,943
Issuance of shares of common stock, amount	315	$ 1	314
Issuance of restricted stock units and net share settlement related to withholding taxes (in shares)		26,265
Issuance of restricted stock units and net share settlement related to withholding taxes, amount	(1,758)	$ 3	(1,761)
Stock-based compensation	6,268		6,268
Net income	161,863
Total other comprehensive (loss) income	11,419
Common stock, issued		104,027,915				36,270,015
Additional paid-in capital			774,232
Retained earnings				1,491,041
Accumulated other comprehensive income					(1,135)
Total stockholders’ equity	508,042	$ 10,403				$ (1,766,499)
Net income	129,152			129,152
Total other comprehensive (loss) income	7,266				7,266
Issuance of shares of common stock (in shares)		34,681
Issuance of shares of common stock, amount	2,846	$ 3	2,843
Issuance of restricted stock units and net share settlement related to withholding taxes (in shares)		37,236
Issuance of restricted stock units and net share settlement related to withholding taxes, amount	(2,270)	$ 4	(2,274)
Stock-based compensation	9,096		9,096
Common stock, issued		104,099,832				36,270,015
Additional paid-in capital			783,897
Retained earnings				1,620,193
Accumulated other comprehensive income					6,131
Total stockholders’ equity	$ 654,132	$ 10,410				$ (1,766,499)
Common stock, issued	104,543,414	104,543,414				36,631,254
Additional paid-in capital	$ 819,642		819,642
Retained earnings	1,778,133			1,778,133
Accumulated other comprehensive income	9,026				9,026
Total stockholders’ equity	800,757	$ 10,455				$ (1,816,499)
Net income	39,399			39,399
Total other comprehensive (loss) income	(4,058)				(4,058)
Issuance of shares of common stock (in shares)		29,717
Issuance of shares of common stock, amount	1,877	$ 3	1,874
Issuance of restricted stock units and net share settlement related to withholding taxes (in shares)		66,809
Issuance of restricted stock units and net share settlement related to withholding taxes, amount	(5,819)	$ 7	(5,826)
Repurchase of common stock (in shares)						1,066,194
Repurchase of common stock, amount	(150,000)					$ (150,000)
Stock-based compensation	10,090		10,090
Net income	101,263
Total other comprehensive (loss) income	(4,690)
Common stock, issued		104,639,940				37,697,448
Additional paid-in capital			825,780
Retained earnings				1,817,532
Accumulated other comprehensive income					4,968
Total stockholders’ equity	692,246	$ 10,465				$ (1,966,499)
Net income	61,864			61,864
Total other comprehensive (loss) income	(632)				(632)
Issuance of shares of common stock (in shares)		124,959
Issuance of shares of common stock, amount	12,484	$ 12	12,472
Issuance of restricted stock units and net share settlement related to withholding taxes (in shares)		28,131
Issuance of restricted stock units and net share settlement related to withholding taxes, amount	(2,335)	$ 3	(2,338)
Repurchase of common stock (in shares)						439,233
Repurchase of common stock, amount	(79,689)		(15,000)			$ (64,689)
Stock-based compensation	$ 7,866		7,866
Common stock, issued	104,793,030	104,793,030				38,136,681
Additional paid-in capital	$ 828,780		$ 828,780
Retained earnings	1,879,396			$ 1,879,396
Accumulated other comprehensive income	4,336				$ 4,336
Total stockholders’ equity	$ 691,804	$ 10,480				$ (2,031,188)