Fair Value equity-based compensation awards and options vested.

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Represents the highest amount of shares that an eligible employee can purchase under the plan per period.

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Represents the maximum expiration term of awards granted under the plan.

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Represents the maximum expiration term of awards granted applicable to holders of a specific percentage of voting rights of all classes of outstanding stock on the date of grant.

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Represents the minimum percentage of voting rights of all classes of outstanding stock, on the date of grant, held by the persons to whom awards were granted for applicability of specific expiration term of options.

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Represents the number of offering periods per annum over which an employee may purchase the shares of common stock of the entity under the stock-based compensation arrangements.

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Represents the shares reserved for grant under option or other awards to the entity's non-employee directors annually under the share-based compensation plan.

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Represents the shares reserved for one-time grant under option or other awards to the entity's non-employee directors under the share-based compensation plan.

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Represents the offering period over which an employee may purchase the shares of common stock of the entity under the stock-based compensation arrangements.

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Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost, Amortization Period

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Represents the term of share-based compensation plans.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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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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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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Number of share instruments newly issued under a share-based compensation plan.

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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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No definition available.

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Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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

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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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Stock-Based Compensation - Narrative (Details)					1 Months Ended			12 Months Ended
Stock-Based Compensation - Narrative (Details)	Aug. 31, 2016 USD ($) shares	Aug. 23, 2016 USD ($) $ / shares shares	Feb. 29, 2016 USD ($) shares	Jan. 01, 2016 shares	May 31, 2015 shares	Jun. 30, 2014 shares	Jun. 30, 2010 USD ($) item shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Options expired in relation to the Offer		456,995
Shares issued in Replacement Offering		334,027
Shares eligible for purchase via options		113,531
Weighted-average exercise price (in dollars per share) \| $ / shares		$ 7.20
Vesting period of replacement options		3 years
Incremental charge resulting from the plan modification \| $		$ 926,000
Amortization period of incremental charge		3 years
Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Unamortized compensation cost, net of expected forfeitures \| $								$ 2,600,000
Weighted average expected period over which the expense is to be recognized								2 years 7 months 6 days
Fair value of vested options and awards \| $								$ 2,000,000
Tax benefits associated with exercise of stock options \| $								0	$ 0	$ 0
Intrinsic value of awards exercised \| $								0	$ 300,000	$ 800,000
RSU's
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Unamortized compensation cost, net of expected forfeitures \| $								$ 600,000
Weighted average expected period over which the expense is to be recognized								2 years
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Number of shares reserved for issuance							200,000
Increase in number of shares reserved for issuance					200,000
Number of offering periods \| item							2
Offering period							6 months
Purchase price to be paid by participants as a percentage of price per share either at the beginning or the end of each six-month offering period, whichever is less							85.00%
Shares of common stock issued under the plan	31,900		37,300
Aggregate purchase price of shares issued \| $	$ 167,000		$ 197,000
Shares authorized and unissued								150,000
Employee stock purchase plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Maximum amount of shares that eligible employee may purchase annually (in dollars) \| $							$ 25,000
Inducement Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Stock options exercised									52,000	7,000
Weighted-average exercise price (in dollars per share) \| $ / shares									$ 43.74	$ 36.78	$ 44.23
Number of shares outstanding									164,000	223,000	318,000
Equity Incentive Plan2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Term of Plan								10 years
Number of shares reserved for issuance									400,000
Increase in number of shares reserved for issuance				50,000
Equity Incentive Plan2010 [Member] \| Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Maximum annual option grants or other awards to the entity's non-employee directors (in shares)								4,000
Maximum one-time grant of an option or other awards to the entitiy's non employee directors (in shares)								12,000
Maximum term of options granted								10 years
Minimum percentage of voting rights required for applicability of a specific expriation term								10.00%
Maximum expiration term of options granted								5 years
Vesting period of replacement options								4 years
Increase in number of shares reserved for issuance						150,000		50,000	50,000	200,000
Equity Incentive Plan2010 [Member] \| Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Term of Plan								6 years
Equity Incentive Plan2010 [Member] \| Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Term of Plan								10 years
Amended 2000 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Shares authorized and unissued								0
Mosy Plans [Member] \| Options
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Stock options exercised									8,000	41,000
Options expired in relation to the Offer								58,000
Shares issued in Replacement Offering								384,000	154,000	17,000
Weighted-average exercise price (in dollars per share) \| $ / shares								$ 13.88	$ 35.14	$ 38.73	$ 38.64
Shares authorized and unissued								114,000	106,000	176,000	42,000
Number of shares outstanding								522,000	675,000	599,000	672,000
Mosy Plans [Member] \| RSU's
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Total intrinsic value of the restricted stock units outstanding \| $								$ 300,000