Commitments and Contingencies - Additional Information (Detail) (USD $)					1 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013 Colorado Before Amendment	Sep. 30, 2013 Colorado After Amendment	Sep. 30, 2013 Pending Litigation	Jul. 15, 2010 Schwab Plaintiff	Oct. 15, 2010 Minimum FHLB Chicago Plaintiff	Sep. 30, 2013 Maximum	Sep. 30, 2012 Maximum	Sep. 30, 2013 Sequoia FHLB Seattle Residential	Sep. 30, 2013 Sequoia Schwab Residential	Sep. 30, 2013 Sequoia FHLB Chicago Residential	Sep. 30, 2013 Sequoia FHLB Chicago First Notice Residential	Sep. 30, 2013 Sequoia FHLB Chicago Second Notice Residential
Loss Contingencies [Line Items]
Future Lease Commitments with expiration date	$ 11,547,000	$ 2,000,000	$ 2,000,000
Operating lease expiration dates							2021
Operating lease expense							1,000,000	1,000,000
Unamortized leasehold improvement	200,000
Statutory interest rate per annum									8.00%		10.00%
Original principal amount of securities									133,000,000	14,800,000		105,000,000	379,000,000
Debt instrument principal payment amount									113,300,000
Debt instrument interest payment amount									11,000,000
Number of other named defendants along with SRF					26	45
Principal balance of securities										12,600,000		71,500,000	256,100,000
Debt instrument interest amount										1,300,000		24,000,000	80,700,000
Possible litigation loss, minimum				0
Possible litigation loss, maximum				$ 25,000,000