Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Value of forfeitures of stock or other type of equity issued of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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Value of stock issued as a result of the exercise of stock options.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Beginning balance at Dec. 31, 2015	$ 513	$ 887,501	$ (10,001)	$ (473,404)	$ (25,047)	$ 379,562
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				159,366		159,366
Tax benefit or Translation adjustment related to adoption of ASU (ASU 2016-09 [Member]) at Dec. 31, 2016				75		75
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), net of income taxes					2,779	2,779
Repurchase of Company stock for retirement	(5)			(24,806)		(24,811)
Payment of dividend		883	(1,541)	(153,036)		(153,694)
Exercise of stock options		1,702				1,702
Restricted stock units and stock options surrendered	2	(3,112)				(3,110)
Stock-based compensation expense		6,128				6,128
Ending balance at Dec. 31, 2016	510	893,102	(11,542)	(491,805)	(22,268)	367,997
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				176,100		176,100
Tax benefit or Translation adjustment related to adoption of ASU (ASU 2014-09 [Member]) at Dec. 31, 2017						(100)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), net of income taxes					(4,424)	(4,424)
Payment of dividend		745	(1,711)	(163,465)		(164,431)
Exercise of stock options		65				65
Restricted stock units and stock options surrendered	2	(3,793)				(3,791)
Stock-based compensation expense		6,640				6,640
Ending balance at Dec. 31, 2017	512	896,759	(13,253)	(479,170)	(26,692)	378,156
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				264,670		264,670
Tax benefit or Translation adjustment related to adoption of ASU (ASU 2014-09 [Member]) at Dec. 31, 2018				(134)		(134)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), net of income taxes					(1,332)	(1,332)
Payment of dividend		514	(1,930)	(173,890)		(175,306)
Exercise of stock options		11				11
Restricted stock units and stock options surrendered	1	(4,145)				(4,144)
Stock-based compensation expense		7,656				7,656
Ending balance at Dec. 31, 2018	$ 513	$ 900,795	$ (15,183)	$ (388,524)	$ (28,024)	$ 469,577