Investment Securities - Total Gross Proceeds from Sales of Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Gross realized gains and losses
Available-for-sale securities, gross realized gains	$ 347	$ 557
Available-for-sale securities, gross realized losses	150	122
Gross realized gains	2	65
Gross realized losses	0	25
Mortgage-backed securities
Gross realized gains and losses
Available-for-sale securities, gross realized gains	45	0
Available-for-sale securities, gross realized losses	0	0
Asset-backed securities
Gross realized gains and losses
Available-for-sale securities, gross realized losses	0	0
State and political securities
Gross realized gains and losses
Available-for-sale securities, gross realized gains	14	299
Available-for-sale securities, gross realized losses	0	0
Other debt securities
Gross realized gains and losses
Available-for-sale securities, gross realized gains	0	32
Available-for-sale securities, gross realized losses	0	81
Financial institution equity securities
Gross realized gains and losses
Available-for-sale securities, gross realized gains	288	82
Available-for-sale securities, gross realized losses	0	0
Gross realized gains	0	6
Gross realized losses	0	13
Non-financial institution equity securities
Gross realized gains and losses
Available-for-sale securities, gross realized gains	0	144
Available-for-sale securities, gross realized losses	150	41
Gross realized gains	2	59
Gross realized losses	$ 0	$ 12

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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This item represents the gain realized during the period from the sale of trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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