CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - 6 months ended Jun. 30, 2017 - USD ($) $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2016	$ 0	$ 39	$ 341,270	$ (119,327)	$ (28,182)	$ (4,502)	$ 189,298
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	0	0	0	28,827	0	4,502	33,329
Cumulative effect of a change in accounting principle - adoption of ASU 2016-09	0	0	74	6,464	0	0	6,538
Exercise of stock options	0	0	2,757	0	0	0	2,757
Tax effect of stock options and restricted stock units	0	0	(1,278)	0	0	0	(1,278)
Share-based employee compensation expense	0	0	3,362	0	0	0	3,362
Balance at Jun. 30, 2017	$ 0	$ 39	$ 346,185	$ (84,036)	$ (28,182)	$ 0	$ 234,006

Amount of the cumulative effect on stockholders' equity, net of related income tax effect.

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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

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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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