Loans and Credit Quality - Average Recorded Investment in Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Impaired [Line Items]
Average recorded investment	$ 93,979	$ 93,415	$ 92,822	$ 93,644
Interest Income Recognized	914	813	1,821	1,605
Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	85,221	83,166	84,194	83,116
Interest Income Recognized	814	757	1,583	1,477
Consumer Loans [Member] \| Single Family [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	83,653	81,754	82,661	81,612
Interest Income Recognized	790	740	1,540	1,444
Consumer Loans [Member] \| Home Equity and Other [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	1,568	1,412	1,533	1,504
Interest Income Recognized	24	17	43	33
Commercial Loans [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	8,758	10,249	8,628	10,528
Interest Income Recognized	100	56	238	128
Commercial Loans [Member] \| Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	4,441	3,125	3,740	3,124
Interest Income Recognized	37	4	96	8
Commercial Loans [Member] \| Multifamily [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	832	1,864	836	1,878
Interest Income Recognized	6	6	12	35
Commercial Loans [Member] \| Construction/Land Development [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	1,105	2,458	1,368	3,023
Interest Income Recognized	21	23	47	44
Commercial Loans [Member] \| Commercial Business [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment	2,380	2,802	2,684	2,503
Interest Income Recognized	$ 36	$ 23	$ 83	$ 41

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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