Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2016	$ 479,517	$ 797	$ 252,957	$ 921,942	$ (683,991)	$ (12,188)
Beginning Balance, Shares at Dec. 31, 2016		79,652
Net income (loss)	23,840			23,840
Other comprehensive income (loss), net of tax	8,893					8,893
Dividend payments ($0.09 per share)	(17,368)			(17,368)
Dividends accrued on unvested restricted stock units	(37)			(37)
Stock options exercised	13,412			(2,827)	16,239
PSUs, RSUs and restricted stock vested	(441)			(3,257)	2,816
Purchase of treasury stock	(17,348)				(17,348)
Stock-based compensation expense	7,433		7,433
ASU 2016-09 adoption	10		125	(115)
Ending Balance at Dec. 31, 2017	497,911	$ 797	260,515	922,178	(682,284)	(3,295)
Ending Balance, Shares at Dec. 31, 2017		79,652
Net income (loss)	(19,342)			(19,342)
ASU adoption (see Note 1) \| ASU 2014-09 [member]	278			278
ASU adoption (see Note 1) \| ASU 2016-01 [Member]	3,220			3,220
Other comprehensive income (loss), net of tax	(11,121)					(11,121)
Dividend payments ($0.09 per share)	(17,267)			(17,267)
Dividends accrued on unvested restricted stock units	(7)			(7)
Stock options exercised	1,483			(603)	2,086
PSUs, RSUs and restricted stock vested	(499)			(4,482)	3,983
Purchase of treasury stock	(15,532)				(15,532)
Stock-based compensation expense	7,155		7,155
Ending Balance at Dec. 31, 2018	$ 446,279	$ 797	267,670	883,975	(691,747)	(14,416)
Ending Balance, Shares at Dec. 31, 2018	79,652	79,652
Net income (loss)	$ (52,982)			(52,982)
ASU adoption (see Note 1) \| ASU 2016-02 [member]	4			4
ASU adoption (see Note 1) \| ASU 2018-02 [Member]				(385)		385
Other comprehensive income (loss), net of tax	(2,386)					(2,386)
Dividend payments ($0.09 per share)	(17,212)			(17,212)
Dividends accrued on unvested restricted stock units	(10)			(10)
Stock options exercised	526			(208)	734
PSUs, RSUs and restricted stock vested	(571)			(6,480)	5,909
Purchase of treasury stock	(184)				(184)
Stock-based compensation expense	6,962		6,962
Ending Balance at Dec. 31, 2019	380,426	$ 797	$ 274,632	$ 806,702	$ (685,288)	$ (16,417)
Ending Balance (ASU 2018-02 [Member]) at Dec. 31, 2019	$ 385
Ending Balance, Shares at Dec. 31, 2019	79,652	79,652

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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