Represents the number of units which management officer elected to invest under the plan.

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The specified number of securities that each class of warrants or rights outstanding give the holder the right but not the obligation to purchase from the issuer at a specific price, on or before a certain date.

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- Definition

The cash outflow to reacquire common stock during the period.

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-Name Accounting Standards Codification

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Number of shares that have been repurchased and retired during the period.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Shareholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended	9 Months Ended
	Aug. 31, 2011 unit	Sep. 30, 2011	Sep. 30, 2010	Aug. 04, 2010
Shareholders' Equity
Number of shares approved to be repurchased under new share repurchase program				2,000,000
Amount paid to repurchase shares under approved share purchase program		$ 23,311	$ 10,457
Number of units the Chief Executive Officer and the General Counsel of the Company elected to invest in	138,375
Number of common shares issuable under each unit in the employer stock fund	1
Number of shares repurchased	2,000,000