Commitments and Contingencies - Additional Information (Detail) $ in Thousands		3 Months Ended	6 Months Ended
	Jul. 15, 2010 Plaintiff	Jun. 30, 2015 USD ($) lease	Jun. 30, 2015 USD ($) loan lease repurchase_request	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Number of noncancelable leases | lease		9	9
Operating lease expiration dates			2021
Future lease commitments with expiration date		$ 11,628	$ 11,628
Operating lease expense				$ 1,000
Percentage of losses assumed on pool of loans sold			1.00%
Risk-sharing arrangement term (years)			10 years
Market valuation changes in fair value of guarantee asset (less than for three months ending June 30, 2015)		1,000
Special Purpose Entities (SPEs) assets		17,000	$ 17,000		$ 19,000
Special Purpose Entities (SPEs) liabilities		6,000	6,000		7,000
Residential repurchase reserve		5,083	$ 5,083		3,724
Residential repurchase requests | repurchase_request			50
Residential repurchase, number of loans repurchased | loan			1
Residential repurchase provisions recorded (less than for six months ended June 30, 2014)			$ 1,000	$ 1,000
Aggregate amount of loss contingency reserves		2,000	2,000		$ 2,000
Schwab
Loss Contingencies [Line Items]
Number of other named defendants along with SRF | Plaintiff	26
Guarantee Obligations
Loss Contingencies [Line Items]
Unpaid principal amount on loans		$ 874,000	$ 874,000
Weighted average original Fair Isaac Corporation (FICO) score		762	762
Weighted average original loan-to-value (LTV)		75.00%	75.00%
Potential future payments on loans		$ 10,000	$ 10,000
Guarantee Obligations | Financing Receivables, Equal To Greater Than 30 Days Past Due
Loss Contingencies [Line Items]
Percent of loans in reference portfolio that are past due			200000000.00%
Residential | Sequoia | FHLB Seattle
Loss Contingencies [Line Items]
Statutory interest rate per annum		8.00%	8.00%
Original principal amount of securities		$ 133,000	$ 133,000
Debt instrument principal payment amount			119,000
Debt instrument interest payment amount			11,000
Residential | Sequoia | Schwab
Loss Contingencies [Line Items]
Original principal amount of securities		15,000	15,000
Principal balance of securities		13,000	13,000
Debt instrument interest amount		1,000	1,000
Other income
Loss Contingencies [Line Items]
Fee income from risk sharing agreement		$ 1,000	2,000
Mortgage banking and investment activities
Loss Contingencies [Line Items]
Market valuation changes in fair value of guarantee asset (less than for three months ending June 30, 2015)			$ (1,000)