Stock Options and Stock-Based Compensation Stock Options Outstanding (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 1995	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at December 31, 2012, Number of Shares	42,000		42,000
Granted in 2013, Number of Shares	0	600,000
Exercised in 2013, Number of Shares	0
Forfeited in 2013, Number of Shares	0
Outstanding at March 31, 2013, Number of Shares	42,000		42,000
Exercisable at March 31, 2013, Number of Shares	42,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at December 31, 2012, Weighted Average Exercise Price (usd per share)	$ 18.00
Granted in 2013, Weighted Average Exercise Price (usd per share)	$ 0.00
Exercised in 2013, Weighted Average Exercise Price (usd per share)	$ 0.00
Forfeited in 2013, Weighted Average Exercise Price (usd per share)	$ 0.00
Outstanding at December 31, 2012, Weighted Average Exercise Price (usd per share)	$ 18.00
Exercisable at March 31, 2013, Weighted Average Exercise Price (usd per share)	$ 18.00
Outstanding at March 31, 2013, Weighted Average Remaining Contratctual Term	2 years 3 months 18 days
Exercisable at March 31, 2013, Weighted Average Remaining Contractual Term	2 years 3 months 18 days
Exercised in 2013, Aggregate Intrinsic Value	$ 0
Outstanding at March 31, 2013, Aggregate Intrinsic Value	0
Exercisable at March 31, 2013, Aggregate Intrinsic Value	$ 0

Total aggregate intrinsic value on shares exercised.

No definition available.

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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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

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- Definition

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

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

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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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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 can acquire the shares reserved for issuance on stock options awarded.

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

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