Available-for-sale Securities, Securities Sold, at Carrying Value

No definition available.

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- Definition

Number of institutions issuing debt.

+ References

No definition available.

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- Definition

Number of securities representing interests in tranches of trusts.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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- Definition

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.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

For any transfer of securities categorized as held-to-maturity, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
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- Definition

This item represents the unrealized gain (loss) recognized in other comprehensive income (a separate component of shareholders' equity) as a result of securities categorized as held-to-maturity being transferred to the available-for-sale securities category.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (c)
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- Definition

This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

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-Name Accounting Standards Codification
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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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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.

+ Details

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Securities - Additional Information (Details)	3 Months Ended		12 Months Ended
Securities - Additional Information (Details)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) institution Tranche	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Transferred security, at carrying value		$ 365,941,000
Transferred to AFS securities, unrealized gain (loss)		$ 13,219,000
Proceeds from sales of securities available for sale			$ 495,340,000	$ 4,028,000	$ 8,444,000
Carrying Value	$ 495,192,000		495,192,000
Gross realized gain (loss), excluding other than temporary impairments			148,000
Carrying value	674,104,000		674,104,000
Securities available for sale, at fair value	671,488,000		$ 671,488,000	674,248,000
Number of securities representing interests in tranches of trusts (tranches) \| Tranche			2
Number of institutions issuing debt (institutions) \| institution			160
Trust preferred securities
Schedule of Available-for-sale Securities [Line Items]
Carrying value	12,442,000		$ 12,442,000	23,749,000
Securities available for sale, at fair value	9,388,000		9,388,000	18,389,000
Other than temporary impairment losses			0	0	0
Secure government, public and trust deposits
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities pledged as collateral	217,867,000		217,867,000	642,447,000
Short-term borrowings
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities pledged as collateral	25,888,000		25,888,000	24,426,000
Metropolitan Securities
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available for sale			36,021,000
Carrying Value	36,021,000		36,021,000
Durbin Amendment Securities
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available for sale	446,971,000
Carrying Value	446,880,000		$ 446,880,000
Gross realized gain (loss), excluding other than temporary impairments	$ 91,000
Non-Heritage Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available for sale				4,028,000	1,213,000
Carrying Value				2,842,000	1,117,000
Gross realized gain (loss), excluding other than temporary impairments				1,186,000	96,000
Heritage Securities
Schedule of Available-for-sale Securities [Line Items]
Proceeds from sales of securities available for sale				$ 7,231,000
Carrying Value					$ 7,231,000