Fair value and the undiscounted amount of the tru-up payment obligation (Detail) (Federal Deposit Insurance Corporation [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Federal Deposit Insurance Corporation [Member]
Business Acquisition, Contingent Consideration [Line Items]
Business Acquisition, Contingent Consideration, at Fair Value	$ 126,345	$ 127,513
Business Acquisition, Contingent Consideration, Potential Cash Payment	$ 176,931	$ 185,372

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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+ Details