Loans Held for Investment, net - Loans Held for Investment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	$ 1,640,853	$ 1,573,020	$ 1,621,554
Unamortized loan fees, net	(753)	(1,544)
Loans held for investment	1,640,100	1,571,476
Allowance for loan losses	(25,147)	(47,037)	(65,182)
Loans held for investment, net	1,614,953	1,524,439
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	529,775	531,131	529,777
Allowance for loan losses	(5,116)	(10,684)	(13,059)
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	25,199	16,514	21,591
Allowance for loan losses	(356)	(1,436)	(6,402)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	766,925	683,509	702,355
Allowance for loan losses	(15,985)	(28,716)	(42,065)
Commercial real estate \| Land and construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	143,419	106,436
Commercial real estate \| Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	318,313	265,735
Commercial real estate \| Retail/office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	161,497	155,095
Commercial real estate \| Other commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	143,696	156,243
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	318,954	341,866	367,831
Allowance for loan losses	(3,690)	(6,201)	$ (3,656)
Consumer loans \| Education
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	91,671	108,384
Consumer loans \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	$ 227,283	$ 233,482

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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