Share-Based Compensation Plans Stock Options (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012 years
Summary of all common stock option activity
Number of Shares Outstanding beginning balance	6,052
Weighted Average Exercise Price Per Share Outstanding beginning balance	$ 9.97
Number of Shares Granted	0
Weighted Average Exercise Price Per Share Granted	$ 0.00
Number of Shares Exercised	(18)
Weighted Average Exercise Price Per Share Exercised	$ 3.93
Number of Shares Forfeited or expired	(634)
Weighted Average Exercise Price Per Share Forfeited or expired	$ 12.59
Number of Shares Outstanding ending balance	5,400
Weighted Average Exercise Price Per Share Outstanding ending balance	$ 9.68
Weighted Average Exercise Price Per Share average contractual term (years)	2.98
Aggregate intrinsic value Outstanding ending balance	$ 1,185
Number of Shares Fully vested and expected to vest	5,384
Weighted Average Exercise Price Per Share Fully vested and expected to vest	$ 9.69
Average Remaining Contractual Term Fully vested and expected to vest (years)	2.97
Aggregate intrinsic value Fully vested and expected to vest	1,185
Number of Shares Exercisable	5,073
Weighted Average Exercise Price Per Share Exercisable	$ 9.83
Average Remaining Contractual Term Exercisable (years)	2.70
Aggregate intrinsic value Exercisable	$ 1,130

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.

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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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The weighted average period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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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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The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited.

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

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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 stock options awarded under the plan during the reporting period.

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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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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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As of the balance sheet date, the total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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