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.

No definition available.

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- Definition

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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- Definition

Amount of liability hedged in fair value hedging relationship.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4EE
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

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Derivative Financial Instruments Impact of Fair Value on Qualifying Hedges (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings		$ 12,389	$ 114
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	$ 0
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	0	0	0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	5,555	6,557	7,885
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	9,571
Operating Expense [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(17,486)	0	0
Interest rate derivatives [Member] \| Operating Expense [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	8,477	10,376	2,702
Interest rate derivatives [Member] \| Operating Expense [Member] \| Not Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	4,241	6,557	7,885
Interest rate derivatives [Member] \| Other Income [Member] \| Not Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	1,314	0	0
Mortgage Banking Derivatives [Member] \| Operating Expense [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(6)	(378)	(2,062)
Other Contract [Member] \| Operating Expense [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	1,100	2,391	(526)
Long-term Debt [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Liability, Fair Value Hedge	317,486			$ 0
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	17,486
Long-term Debt [Member] \| Operating Expense [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 17,486	$ 0	$ 0