Loans (Activity Related to Accretable Yield of Loans Acquired With Evidence of Credit Quality Deterioration Since Origination) (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Accretable yield, beginning balance		$ 63,902	$ 79,102
Acquisitions		1,141	898
Accretable yield amortized to interest income		(5,457)	(6,105)
Accretable yield amortized to indemnification asset	[1]	(2,171)	(3,576)
Reclassification from non-accretable difference	[2]	4,193	1,103
Decreases in interest cash flows due to payments and changes in interest rates		(2,390)	(1,224)
Accretable yield, ending balance	[3]	59,218	$ 70,198
Accretable yield, to be amortized to indemnification asset		$ 4,800

[1] Represents the portion of the current period accreted yield, resulting from lower expected losses, applied to reduce the loss share indemnification asset.

[2] Reclassification is the result of subsequent increases in expected principal cash flows.

[3] As of March 31, 2016, the Company estimates that the remaining accretable yield balance to be amortized to the indemnification asset for the bank acquisitions is $4.8 million. The remainder of the accretable yield related to bank acquisitions is expected to be amortized to interest income.