Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	$ 1,450	$ 112	$ 2,556	$ 1,059
Gross Realized Losses	(14)	(36)	(14)	(36)
Net Gains (Losses)	1,436	76	2,542	1,023
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	1,305	4	2,350	737
Gross Realized Losses	0	(10)	0	(10)
Net Gains (Losses)	1,305	(6)	2,350	727
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	145	108	206	322
Gross Realized Losses	(14)	(26)	(14)	(26)
Net Gains (Losses)	$ 131	$ 82	$ 192	$ 296

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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