Carrying amount and classification of assets related to the Corporation's variable interests in non-consolidated VIEs and maximum exposure to loss (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	$ 40,386	$ 46,308
Liabilities	(9,427)	(3,621)
Net assets	30,959	42,687
Variable Interest Entity Entity Maximum Loss Exposure Amount	30,959	42,687
PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	181,411	191,197
Liabilities	(31,357)	(20,808)
Net assets	150,054	170,389
Variable Interest Entity Entity Maximum Loss Exposure Amount	150,054	170,389
Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	111,431	114,853
Variable Interest Entity Entity Maximum Loss Exposure Amount	111,431	114,853
Loan | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	15,482	19,647
Loan | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	149,185	160,283
Acquisition Loan [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	0	3,233
Acquisition Loan [Member] | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	143,279	157,660
Advances Working Capital Line [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	0	390
Advances Working Capital Line [Member] | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	1,641	1,196
Advances Advance Facility [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	15,482	16,024
Advances Advance Facility [Member] | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	4,265	1,427
Accrued Income Receivable [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	53	65
Accrued Income Receivable [Member] | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	417	436
Other Assets Member | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	1,783	1,416
Other Advances [Member] | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	1,783	1,416
Equity Method Investments [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	24,851	26,596
Equity Method Investments [Member] | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	31,809	30,478
Servicing Asset At Fair Value Amount [Member] | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	109,648	113,437
Mortgage Servicing Rights [Member] | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	109,648	113,437
Deposits Member | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Liabilities	(9,427)	(3,621)
Deposits Member | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Liabilities	$ (31,357)	$ (20,808)