Changes in Residential and Securitized Mortgage Servicing Rights (Detail) (USD $) In Thousands, unless otherwise specified			3 Months Ended				6 Months Ended				3 Months Ended	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Mortgage Servicing Rights Residential		Jun. 30, 2013 Mortgage Servicing Rights Residential		Jun. 30, 2014 Mortgage Servicing Rights Residential		Jun. 30, 2013 Mortgage Servicing Rights Residential		Jun. 30, 2013 Securitized Mortgage Servicing Rights	Jun. 30, 2013 Securitized Mortgage Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Carrying value, beginning of period	$ 228,815	$ 241,018	$ 238,004		$ 172,849		$ 241,018		$ 144,520		$ 129	$ 193
Additions			7,175		23,072		13,983		54,673
Due to changes in valuation assumptions			(535)		34,754		(492)		47,848
Increase (decrease) in fair value, due to other changes			(15,829)	[1]	(15,716)	[1]	(25,694)	[1]	(32,082)	[1]
Amortization											(33)	(97)
Carrying value, end of period	$ 228,815	$ 241,018	$ 228,815		$ 214,959		$ 228,815		$ 214,959		$ 96	$ 96

[1] Net servicing cash flows, including loan payoffs, and the passage of time.