Changes in the carrying amount and the accretable yield for the other acquired loans (Detail) - SOP Other Loans Acquired [Member] - Internal Credit Assessment [Domain] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accretable yield
Beginning Balance	$ 158,424	$ 67,285	$ 116,304	$ 49,398
Additions	5,406	4,060	56,068	11,144
Accretion	(4,633)	(2,552)	(7,856)	(4,926)
Change In Expected Cash Flows	2,962	8,034	(2,357)	21,211
Ending Balance	162,159	76,827	162,159	76,827
Carrying amount of loans
Beginning Balance	363,097	190,216	212,763	173,659
Additions	17,089	13,139	174,180	33,181
Accretion	4,633	2,552	7,856	4,926
Collections	(16,532)	(6,866)	(26,512)	(12,725)
Ending Balance	368,287	199,041	368,287	199,041
Less: Allowance for loan losses	(16,842)	(15,751)	(16,842)	(15,751)
Carrying amount, net of allowance	$ 351,445	$ 183,290	$ 351,445	$ 183,290