CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (unaudited) (Parenthetical)	3 Months Ended
Mar. 31, 2012
Statement of Stockholders' Equity [Abstract]
Exercise of stock options (in shares)	81,425
Withholdings from vesting of restricted stock	49,855

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

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

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