Stockholders' Equity (Summary of the Changes in Stockholders' Equity) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Balance	$ 329,255
Beginning balance adjustment to retained earnings as a result of the adoption of ASU 2016-09			$ 872
Adjusted stockholders' equity as of January 1, 2017	330,127
Net (loss) income	893	$ 2,489
Accumulated other comprehensive income	466
Issuance of common stock in connection with the Company's equity plans	(2,173)
Treasury stock acquired	(8,203)
Balance	325,561
Nonemployee
Share-based compensation expense	$ 4,451

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 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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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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Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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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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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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