Additional disclosures on cash flow information and non-cash activities (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Dec. 31, 2013
Cash Flow Noncash Investing And Financing Activities Disclosure Abstract
Transfers Of Loans To Other Real Estate Owned	$ 118,098		$ 188,275
Transfers Of Loans To Other Property	30,062		24,974
Total loans transferred to foreclosed assets	148,160		213,249
Transfer Of Portfolio Loans And Leases To Held For Sale 1	2,114,589		442,003
Transfer Of Loans Held For Sale To Portfolio Loans 1	3,913		25,245
Noncash Transfer To Securities From Loans Resulting From Securitization	695,416	[1]	1,149,199	[1]
Trades receivables from brokers and counterparties	77,618		85,746		71,680
Trades Payables To Brokers And Counterparties	654		161,452
Recognition of mortgage servicing rights on securitizations or asset transfers	9,611		15,062
Loans sold to a joint venture in exchange for an acquisition loan and an equity interest in the join venture	$ 0		$ 194,514

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