Consolidated Statements of Stockholders' Deficit - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Loss	Treasury Stock
Common stock, shares, outstanding, beginning (in shares) at Dec. 31, 2017		17,993,000
Stockholders' equity balance, beginning of the period at Dec. 31, 2017	$ (215,540)	$ 250	$ 276,408	$ (69,940)	$ (105)	$ (422,153)
Treasury stock, shares, beginning (in shares) at Dec. 31, 2017						7,029,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	17,073			17,073
Other comprehensive gain (loss)	47				47
Purchase of Company common stock (in shares)		(139,000)				(139,000)
Purchase of Company common stock	(10,003)					$ (10,003)
Reissuance of treasury stock (in shares)		77,000				77,000
Reissuance of treasury stock	456		(2,495)			$ 2,951
Net issuance of shares for stock plans (in shares)		6,000
Net issuance of shares for stock plans	0
Repurchase of restricted shares for taxes (in shares)		(15,000)
Repurchase of restricted shares for taxes	(1,083)		(1,083)
Stock-based compensation	3,368		3,368
Dividends on common stock in excess of retained earnings	(11,204)		(11,204)
Common stock, shares, outstanding, ending (in shares) at Mar. 31, 2018		17,922,000
Stockholders' equity balance, ending of the period at Mar. 31, 2018	$ (216,886)	$ 250	264,994	(52,867)	(58)	$ (429,205)
Treasury stock, shares, ending (in shares) at Mar. 31, 2018						7,091,000
Common stock, shares, outstanding, beginning (in shares) at Dec. 31, 2018	17,644,267	17,644,000
Stockholders' equity balance, beginning of the period at Dec. 31, 2018	$ (202,273)	$ 250	237,726	10,414	(60)	$ (450,603)
Treasury stock, shares, beginning (in shares) at Dec. 31, 2018	7,340,631					7,341,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 31,643			31,643
Other comprehensive gain (loss)	(1)				(1)
Purchase of Company common stock (in shares)		(151,000)				(151,000)
Purchase of Company common stock	$ (12,015)					$ (12,015)
Reissuance of treasury stock (in shares)	168,047	168,000				168,000
Reissuance of treasury stock	$ 6,768		(667)			$ 7,435
Net issuance of shares for stock plans (in shares)		9,000
Net issuance of shares for stock plans	0
Repurchase of restricted shares for taxes (in shares)		(19,000)
Repurchase of restricted shares for taxes	(1,817)		(1,817)
Stock-based compensation	4,107		4,107
Dividends on common stock	$ (12,203)		236	(12,439)
Common stock, shares, outstanding, ending (in shares) at Mar. 31, 2019	17,650,765	17,651,000
Stockholders' equity balance, ending of the period at Mar. 31, 2019	$ (190,821)	$ 250	$ 239,585	$ 24,588	$ (61)	$ (455,183)
Treasury stock, shares, ending (in shares) at Mar. 31, 2019	7,323,900					7,324,000