Loans and Credit Quality - TDR Re-defaults (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) loan	Mar. 31, 2017 USD ($) 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	6	1
Recorded investment \| $	$ 884	$ 270
Consumer loans [Member] \| Single family [Member]
TDR balances which have subsequently re-defaulted
Number of TDR loan relationships that re-defaulted \| loan	6	1
Recorded investment \| $	$ 884	$ 270

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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- Definition

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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