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	Jun. 30, 2014	Dec. 31, 2013
Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Liabilities	$ (3,596)	$ (3,621)
Net assets	29,162	42,687
Variable Interest Entity Entity Maximum Loss Exposure Amount	29,162	42,687
PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	163,044	191,197
Liabilities	(20,871)	(20,808)
Net assets	142,173	170,389
Variable Interest Entity Entity Maximum Loss Exposure Amount	142,173	170,389
Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	110,493	114,853
Variable Interest Entity Entity Maximum Loss Exposure Amount	110,493	114,853
Loan | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	7,910	19,647
Loan | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	130,603	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	122,536	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	518	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	1,099	1,196
Advances Advance Facility [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	7,392	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	6,968	1,427
Accrued Income Receivable [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	30	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	362	436
Other Assets Member | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	2,075	1,416
Other Advances [Member] | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	2,075	1,416
Equity Method Investments [Member] | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	24,818	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	32,079	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	108,418	113,437
Mortgage Servicing Rights [Member] | Fnma Gnma Fhlmc Vie [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	108,418	113,437
Deposits Member | Prlp2011 Holdings Llc Joint Venture [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Assets	32,758	46,308
Liabilities	(3,596)	(3,621)
Deposits Member | PR Asset Portfolio 2013-1 International, LLC [Member]
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Liabilities	$ (20,871)	$ (20,808)