Note Supplemental disclosure on the consolidated statments of cash flows (Additional disclosures on cash flow information and non-cash activities) (Detail) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Cash Flow Noncash Investing And Financing Activities Disclosure Abstract
Transfers Of Loans To Other Real Estate Owned		$ 62,409	$ 67,199
Transfers Of Loans To Other Property		15,442	19,103
Total loans transferred to foreclosed assets		77,851	86,302
Transfer Of Portfolio Loans And Leases To Held For Sale 1		0	61,290
Transfer Of Loans Held For Sale To Portfolio Loans 1		4,220	8,523
Account receivable from sale of loans		14,477	0
Transfers Of Trading Securities To Available For Sale Securities		0	5,523
Noncash Transfer To Securities From Loans Resulting From Securitization	[1]	383,441	517,265
Trades receivables from brokers and counterparties		78,994	111,964	$ 78,759
Trades Payables To Brokers And Counterparties		43,142	73,155
Recognition of mortgage servicing rights on securitizations or asset transfers		$ 5,023	$ 7,302

[1] Includes loans securitized into trading securities and subsequently sold before quarter end.