Time deposits (Narrative) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Time Deposits, Type [Line Items]
Time deposits	$ 22,700,000	$ 32,500,000
Wholesale Brokered Time Deposits
Time Deposits, Type [Line Items]
Wholesale brokered deposits	0	0
Internet Listing Service Deposits
Time Deposits, Type [Line Items]
Interest-bearing Domestic Deposit, Other Time Deposit	$ 11,000,000	$ 0

[Line Items] for Time Deposits by Type

No definition available.

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- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Amount of interest-bearing domestic deposit liabilities classified as other. Excludes certificates of deposit.

+ References

+ Details

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

+ Details

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- Details

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- Details

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