Subsequent Event - Additional Information (Detail) In Millions, unless otherwise specified		1 Months Ended
	Jun. 30, 2012 Maximum	Jul. 19, 2012 Subsequent Event	Jul. 24, 2012 Subsequent Event	Jul. 24, 2012 Subsequent Event Maximum
Subsequent Event [Line Items]
Number of shares that may be repurchased under current share repurchase plan	15			20
Number of shares available to be repurchased under current share repurchase plan			10.3
Stock purchase plan expiration date			Apr. 30, 2014
Processing services term		6 years