The fair value of available-for-sale securities that serve as collateral for borrowings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5086-111524

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26805-111562

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- Definition

The carrying amount of held-to-maturity securities that serve as collateral for borrowings.

+ 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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Securities (Details) - Narrative - USD ($)	12 Months Ended
Securities (Details) - Narrative - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-Sale Securities [Line Items]
Available-for-sale securities pledged as collateral	$ 1,100,000,000	$ 856,900,000
Held-to-maturity securities pledged as collateral	0	0
Net realized gains on sales of securities	1,420,000	2,373,000	$ 8,125,000
Municipal securities
Schedule of Available-for-Sale Securities [Line Items]
Net realized gains on sales of securities	1,100,000
MBSs and CMOs
Schedule of Available-for-Sale Securities [Line Items]
Net realized gains on sales of securities	$ 304,000
Available-for-sale securities, excluding other mortgage-backed securities
Schedule of Available-for-Sale Securities [Line Items]
Net realized gains on sales of securities		521,000
CDOs
Schedule of Available-for-Sale Securities [Line Items]
Net realized gains on sales of securities		$ 1,900,000	3,500,000
Equity securities
Schedule of Available-for-Sale Securities [Line Items]
Net realized gains on sales of securities			$ 4,600,000