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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, before allowance and fees, of loans and leases receivable. Excludes 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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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Loans and Credit Quality - Loans Held for Investment (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Loans held for investment
Total loans before fees and costs	$ 4,183,039	$ 3,849,451
Net deferred loan fees and costs	9,521	3,577
Total loans	4,192,560	3,853,028
Allowance for loan losses	(36,136)	(34,001)	$ (32,656)
Loans held for investment	4,156,424	3,819,027
Fair value of loans held for investment	5,134	17,988
Consumer Loans [Member]
Loans held for investment
Total loans before fees and costs	1,562,735	1,443,696
Consumer Loans [Member] \| Single Family [Member]
Loans held for investment
Total loans before fees and costs	1,148,229	1,083,822
Consumer Loans [Member] \| Home Equity and Other [Member]
Loans held for investment
Total loans before fees and costs	414,506	359,874
Commercial Loans [Member]
Loans held for investment
Total loans before fees and costs	2,620,304	2,405,755
Commercial Loans [Member] \| Commercial Real Estate [Member]
Loans held for investment
Total loans before fees and costs	942,122	871,563
Commercial Loans [Member] \| Multifamily [Member]
Loans held for investment
Total loans before fees and costs	780,602	674,219
Commercial Loans [Member] \| Construction/Land Development [Member]
Loans held for investment
Total loans before fees and costs	648,672	636,320
Commercial Loans [Member] \| Commercial Business [Member]
Loans held for investment
Total loans before fees and costs	248,908	223,653
Fair Value, Measurements, Recurring [Member]
Loans held for investment
Fair value of loans held for investment	5,134	17,988
Level 3 [Member] \| Fair Value, Measurements, Recurring [Member]
Loans held for investment
Fair value of loans held for investment	$ 5,134	$ 17,988