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, 2015	$ 480,160	$ 797	$ 246,879	$ 906,772	$ (665,319)	$ (8,969)
Beginning Balance, Shares at Dec. 31, 2015		79,652
Net income (loss)	35,229			35,229
Other comprehensive income (loss), net of tax	(3,219)					(3,219)
Dividend payments	(17,583)			(17,583)
Dividends accrued on unvested restricted stock units	(48)			(48)
Stock options exercised	4,717			(1,499)	6,216
PSUs, RSUs and restricted stock vested	(142)		(142)	(929)	929
Purchase of treasury stock	(25,817)				(25,817)
Income tax effect of stock compensation arrangements	(475)		(475)
Stock-based compensation expense	6,695		6,695
Ending Balance at Dec. 31, 2016	479,517	$ 797	252,957	921,942	(683,991)	(12,188)
Ending 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	(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)
Income tax effect of stock compensation arrangements	10		125	(115)
Stock-based compensation expense	7,433		7,433
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	79,652
Net income (loss)	$ (19,342)			(19,342)
ASU adoption	(3,220)
ASU adoption \| ASU 2014-09 [member]	278			278
ASU adoption \| ASU 2016-01 [Member]	3,220			3,220
Other comprehensive income (loss), net of tax	(11,121)					(11,121)
Dividend payments	(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

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The adjustment for RSUs is subject to a market condition based on the company's relative total shareholder return against all companies in the measured Index at the end of a performance period. The fair value of the award is based on the market price of our common stock on the date of grant, adjusted for the expected outcome of the impact of market conditions using a Monte Carlo Simulation valuation method.

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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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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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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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