Loans and Credit Quality - Activity in Allowance for Credit Losses by Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Allowance for credit losses by loan portfolio
Beginning Balance	$ 42,913	$ 39,116
Charge-offs	(46)	(98)
Recoveries	169	678
(Reversal of) Provision	1,500	750
Ending Balance	44,536	40,446
Consumer loans [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	15,929	16,493
Charge-offs	(46)	(97)
Recoveries	158	356
(Reversal of) Provision	(60)	(557)
Ending Balance	15,981	16,195
Consumer loans [Member] \| Single family [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	8,217	9,412
Charge-offs	0	0
Recoveries	85	280
(Reversal of) Provision	(112)	(484)
Ending Balance	8,190	9,208
Consumer loans [Member] \| Home equity and other [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	7,712	7,081
Charge-offs	(46)	(97)
Recoveries	73	76
(Reversal of) Provision	52	(73)
Ending Balance	7,791	6,987
Commercial real estate loans [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	20,789	17,327
Charge-offs	0	0
Recoveries	4	171
(Reversal of) Provision	1,394	939
Ending Balance	22,187	18,437
Commercial real estate loans [Member] \| Non-owner occupied commercial real estate [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	5,496	4,755
Charge-offs	0	0
Recoveries	0	0
(Reversal of) Provision	680	(128)
Ending Balance	6,176	4,627
Commercial real estate loans [Member] \| Multifamily [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	5,754	3,895
Charge-offs	0	0
Recoveries	0	0
(Reversal of) Provision	606	756
Ending Balance	6,360	4,651
Commercial real estate loans [Member] \| Construction/land development [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	9,539	8,677
Charge-offs	0	0
Recoveries	4	171
(Reversal of) Provision	108	311
Ending Balance	9,651	9,159
Commercial and industrial loans [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	6,195	5,296
Charge-offs	0	(1)
Recoveries	7	151
(Reversal of) Provision	166	368
Ending Balance	6,368	5,814
Commercial and industrial loans [Member] \| Owner occupied commercial real estate [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	3,282	2,960
Charge-offs	0	0
Recoveries	0	0
(Reversal of) Provision	22	6
Ending Balance	3,304	2,966
Commercial and industrial loans [Member] \| Commercial business [Member]
Allowance for credit losses by loan portfolio
Beginning Balance	2,913	2,336
Charge-offs	0	(1)
Recoveries	7	151
(Reversal of) Provision	144	362
Ending Balance	$ 3,064	$ 2,848

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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 (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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