Changes in Residential and Securitized Mortgage Servicing Rights (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Carrying value, end of period	$ 241,018		$ 144,713
Mortgage Servicing Rights Residential
Finite-Lived Intangible Assets [Line Items]
Carrying value, beginning of year	144,520		116,416
Additions	80,799		116,407
Due to changes in interest rates and valuation assumptions	70,218		(20,938)
Increase (decrease) in fair value, due to other changes	(54,519)	[1]	(67,365)	[1]
Carrying value, end of period	241,018		144,520
Securitized Mortgage Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Carrying value, beginning of year	193		596
Amortization	(193)		(403)
Carrying value, end of period			$ 193

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