Allowance for Loan Losses - Recorded Investment Segregated by Amounts Individually or Collectively in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	$ 1,036,547	$ 984,346
Balance, end of period: Individually evaluated for impairment	27,182	31,714
Balance, end of period: Collectively evaluated for impairment	1,009,365	952,632
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	396,901	341,091
Balance, end of period: Individually evaluated for impairment	17,640	24,189
Balance, end of period: Collectively evaluated for impairment	379,261	316,902
Real estate construction one-to-four family
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	37,126	36,828
Balance, end of period: Individually evaluated for impairment	1,473	0
Balance, end of period: Collectively evaluated for impairment	35,653	36,828
Real estate construction other
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	60,697	71,658
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	60,697	71,658
Real estate term owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	126,381	125,795
Balance, end of period: Individually evaluated for impairment	5,846	5,253
Balance, end of period: Collectively evaluated for impairment	120,535	120,542
Real estate term non-owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	330,592	324,198
Balance, end of period: Individually evaluated for impairment	214	760
Balance, end of period: Collectively evaluated for impairment	330,378	323,438
Real estate term other
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	44,821	41,746
Balance, end of period: Individually evaluated for impairment	1,626	1,063
Balance, end of period: Collectively evaluated for impairment	43,195	40,683
Consumer secured by 1st deeds of trust
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	15,943	19,234
Balance, end of period: Individually evaluated for impairment	290	449
Balance, end of period: Collectively evaluated for impairment	15,653	18,785
Consumer other
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance, end of period	24,086	23,796
Balance, end of period: Individually evaluated for impairment	93	0
Balance, end of period: Collectively evaluated for impairment	$ 23,993	$ 23,796

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No definition available.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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