Share-Based Compensation Stock Option Activity (Details) - Employee Stock Option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
A summary of option activity for the period [Roll Forward]
Number of options outstanding, beginning of period	598
Number of options, exercised	0	0
Number of options, forfeitures	(398)
Number of options outstanding, end of period	200	598
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	0
Share based payment award, options, additional disclosures [Abstract]
Weighted-average exercise price, outstanding at beginning of period	$ 12.59
Weighted average exercise price, exercised	0.00
Weighted average exercise price, forfeitures	10.42
Weighted average exercise price, outstanding at end of period	16.92	$ 12.59
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 0.00
Weighted average remaining contractual term	10 months 22 days	10 months 28 days
Aggregate intrinsic value, outstanding	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 0

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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-Publisher FASB
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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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