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

No definition available.

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- Definition

Debt Securities, Number of Investments Sold in Period

+ References

No definition available.

+ Details

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- Definition

Number of institutions issuing debt.

+ References

No definition available.

+ Details

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- Definition

Number of securities representing interests in tranches of trusts.

+ References

No definition available.

+ Details

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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- Definition

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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+ Details

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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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- Details

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- Details

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- Details

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Securities - Additional Information (Details)	3 Months Ended	12 Months Ended
Securities - Additional Information (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) Tranche institution	Dec. 31, 2017 USD ($) Investment	Dec. 31, 2016 USD ($)
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of securities available for sale		$ 2,387,000	$ 495,340,000	$ 4,028,000
Debt securities, AFS, realized gain (loss)		(16,000)	148,000	1,186,000
Amortized Cost	$ 674,104,000	1,264,529,000	674,104,000
Securities available for sale, at fair value	671,488,000	$ 1,250,777,000	671,488,000
Number of securities representing interests in tranches of trusts (tranches) \| Tranche		2
Number of institutions issuing debt (institutions) \| institution		160
Trust preferred securities
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of securities available for sale			9,346,000
Debt securities, AFS, realized gain (loss)			57,000
Amortized Cost	12,442,000	$ 12,359,000	12,442,000
Securities available for sale, at fair value	9,388,000	10,633,000	$ 9,388,000
Number of investments sold in period \| Investment			1
Other than temporary impairment losses		0	$ 0	$ 0
Secure government, public and trust deposits
Debt Securities, Available-for-sale [Line Items]
Debt securities, AFS, restricted	217,867,000	619,308,000	217,867,000
Short-term borrowings
Debt Securities, Available-for-sale [Line Items]
Debt securities, AFS, restricted	25,888,000	$ 18,299,000	25,888,000
Metropolitan Securities
Debt Securities, Available-for-sale [Line Items]
Carrying Value	36,021,000		36,021,000
Proceeds from sales of securities available for sale			36,021,000
Durbin Amendment Securities
Debt Securities, Available-for-sale [Line Items]
Carrying Value	446,880,000		$ 446,880,000
Proceeds from sales of securities available for sale	446,971,000
Debt securities, AFS, realized gain (loss)	$ 91,000