CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock Cumulative Effect, Period of Adoption, as Adjusted	Common Stock	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, as Adjusted	Retained Earnings	Treasury Stock Cumulative Effect, Period of Adoption, as Adjusted	Treasury Stock	Accumulated Other Comprehensive Loss	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, as Adjusted	Total
Increase (Decrease) in Stockholders' Equity
Change in accounting principle and other			$ (11,639)						$ (11,639)
Balance at Dec. 31, 2019	$ 686,806	$ 686,806		$ 2,067,540	$ 2,079,179	$ (590,971)	$ (590,971)			$ 2,163,375	$ 2,175,014
Balance (in shares) at Dec. 31, 2019	81,743,000	81,743,000				(31,420,000)	(31,420,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					(8,515)						(8,515)
Exercise of common stock options and vested employee stock awards		$ 38									$ 38
Exercise of common stock options and vested employee stock awards (in shares)		287,000									2,578
Employee income tax paid on vested equity awards							$ (6,165)				$ (6,165)
Employee income tax paid on vested equity awards (in shares)							(108,000)
Sale of common stock under employee stock purchase plan		$ 2,781									2,781
Sale of common stock under employee stock purchase plan (in shares)		65,000
Stock based compensation expense		$ 6,802									6,802
Treasury stock purchases							$ (20,000)				(20,000)
Treasury stock purchases (in shares)							(386,000)
Cash dividends declared					(7,019)						(7,019)
Warrants issued to U.S. Treasury		8,248									8,248
Balance at Dec. 31, 2020		$ 704,675			2,052,006		$ (617,136)				2,139,545
Balance (in shares) at Dec. 31, 2020		82,095,000					(31,914,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					111,910						111,910
Exercise of common stock options and vested employee stock awards		$ 606									$ 606
Exercise of common stock options and vested employee stock awards (in shares)		177,000									41,020
Employee income tax paid on vested equity awards							$ (1,576)				$ (1,576)
Employee income tax paid on vested equity awards (in shares)							(42,000)
Sale of common stock under employee stock purchase plan		$ 2,540									2,540
Sale of common stock under employee stock purchase plan (in shares)		64,000
Stock based compensation expense		$ 8,685									8,685
Warrants issued to U.S. Treasury		5,804									5,804
Balance at Dec. 31, 2021		$ 722,310			2,163,916		$ (618,712)				2,267,514
Balance (in shares) at Dec. 31, 2021		82,336,000					(31,956,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					72,953						72,953
Exercise of common stock options and vested employee stock awards		$ 142									$ 142
Exercise of common stock options and vested employee stock awards (in shares)		151,000									9,817
Employee income tax paid on vested equity awards							$ (1,150)				$ (1,150)
Employee income tax paid on vested equity awards (in shares)							(38,000)
Sale of common stock under employee stock purchase plan		$ 2,815									2,815
Sale of common stock under employee stock purchase plan (in shares)		106,000
Stock based compensation expense		$ 9,159									9,159
Net unrealized depreciation on marketable securities, net of tax								$ (3,802)			(3,802)
Balance at Dec. 31, 2022		$ 734,426			$ 2,236,869		$ (619,862)	$ (3,802)			$ 2,347,631
Balance (in shares) at Dec. 31, 2022		82,593,000					(31,994,000)