Share-Based Compensation (Annual and Quarter) (Detail) - Changes in the stock option plans (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Number of Shares Authorized,Balance		29,000	39,000	39,000
Number of Shares Granted,Balance		12,000	23,000	26,000
Number of Shares Available,Balance		17,000	16,000	13,000
Weighted Average Exercise Price, Balance (in Dollars per share)	$ 5.73	$ 4.99	$ 4.51	$ 4.57
Expired		(10,000)
Expired		(11,000)	(3,000)
Expired		1,000	3,000
Expired (in Dollars per share)	$ 2.17	$ 3.97	$ 5.03

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

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-Publisher FASB

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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.

+ References

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

+ References

No definition available.

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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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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