Investment Securities - Trading Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized cost	$ 218	$ 56
Trading securities accumulated gross unrealized gain before tax	7	2
Trading securities accumulated gross unrealized loss before tax	(15)	0
Trading securities fair value	210	58
Financial institution equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized cost	61	0
Trading securities accumulated gross unrealized gain before tax	3	0
Trading securities accumulated gross unrealized loss before tax	(1)	0
Trading securities fair value	63	0
Non-financial institution equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized cost	157	56
Trading securities accumulated gross unrealized gain before tax	4	2
Trading securities accumulated gross unrealized loss before tax	(14)	0
Trading securities fair value	$ 147	$ 58

Trading Securities Accumulated Gross Unrealized Gain Before Tax

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- Definition

Trading Securities Accumulated Gross Unrealized Loss Before Tax

+ References

No definition available.

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+ References

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- Definition

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Cost of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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