Loans and Credit Quality - TDR Re-defaults (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 USD ($) loan	Jun. 30, 2017 USD ($) loan	Jun. 30, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of days past due for consumer loans TDR to be re-default			60 days
Number of days past due for commercial loans TDR to be re-default			90 days
TDR balances which have subsequently re-defaulted
Number of TDR loan relationships that re-defaulted \| loan	7	9	8	10
Recorded investment \| $	$ 1,382	$ 2,460	$ 1,652	$ 2,731
Consumer Loans [Member] \| Single Family [Member]
TDR balances which have subsequently re-defaulted
Number of TDR loan relationships that re-defaulted \| loan	7	8	8	9
Recorded investment \| $	$ 1,382	$ 2,367	$ 1,652	$ 2,638
Consumer Loans [Member] \| Home Equity and Other [Member]
TDR balances which have subsequently re-defaulted
Number of TDR loan relationships that re-defaulted \| loan	0	1	0	1
Recorded investment \| $	$ 0	$ 93	$ 0	$ 93

Re-defaulted troubled debt restructurings on financing receivable.

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- Definition

Trouble Debt Restructuring, Re-Default, Number Of Days Past Due, Commercial

+ References

No definition available.

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Trouble Debt Restructuring, Re-Default, Number of Days Past Due, Consumer

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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