Common Stock and Stock Compensation - Stock Option Activity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Stock Options, Outstanding [Roll Forward]
Outstanding as of December 31, 2012 (shares)	208,862
Granted (shares)	40,293
Exercised (shares)	(23,505)
Canceled (shares)	(92,072)
Outstanding as of December 31, 2013 (shares)	133,578
Vested or expected to vest at December 31, 2013 (shares)	121,170
Exercisable at December 31, 2013 (shares)	81,090
Stock Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding as of December 31, 2012, Weighted Average Exercise Price (dollars per share)	$ 20.75
Granted, Weighted Average Exercise Price (dollars per share)	$ 15.67
Exercised, Weighted Average Exercise Price (dollars per share)	$ 13.14
Canceled, Weighted Average Exercise Price (dollars per share)	$ 25.07
Outstanding as of December 31, 2013, Weighted Average Exercise Price (dollars per share)	$ 17.57
Vested and expected to vest at December 31, 2013, Weighted Average Exercise Price (dollars per share)	$ 17.63
Exercisable at December 31, 2013, Weighted Average Exercise Price (dollars per share)	$ 17.53
Stock Options, Additional Disclosures [Abstract]
Outstanding as of December 31, 2013, Weighted-Average Remaining Contractual Term (in years)	7 years 4 months 24 days
Vested and expected to vest at December 31, 2013, Weighted-Average Remaining Contractual Term (in years)	7 years 3 months 18 days
Exercisable at December 31, 2013, Weighted-Average Remaining Contractual Term (in years)	6 years 4 months 24 days
Outstanding as of December 31, 2013, Aggregate Intrinsic Value	$ 365
Vested and expected to vest at December 31, 2013, Aggregate Intrinsic Value	340
Exercisable at December 31, 2013, Aggregate Intrinsic Value	$ 266

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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.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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

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