LOAN PORTFOLIO - Corporation's TDR Activity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015		Sep. 30, 2014
Schedule Of Financing Receivables [Line Items]
Beginning Balance of TDRs	$ 634,761	$ 628,233	$ 694,453	[1]	$ 630,258
New TDRs	30,044	94,864	95,840		149,609
Increases to existing TDRs (disbursements)	309	1,197	644		1,331
Charge-offs post modification	(5,327)	(12,598)	(58,707)	[2]	(39,246)
Sales	0		(44,048)
Foreclosures	(6,139)	(768)	(16,391)		(3,369)
Transfer Of Trouble Debt Restructuring Loans Held For Sale To Portfolio Loans	40,005		40,005
Paid-off and partial payments	(11,690)	(9,785)	(29,833)		(37,440)
Ending balance of TDRs	$ 681,963	$ 701,143	$ 681,963		$ 701,143

[1] Excludes TDRs held for sale amounting to $45.7 million as of December 31, 2014.

[2] For the nine-month period ended September 30, 2015 includes $45.3 million of charge-offs related to TDRs included in the bulk sale of assets.