Derivative Financial Instruments - Interest Swap Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 829,784		$ 840,646
Fair Value	(80,850)		(37,939)
Interest expense	21,226	$ 18,755
Interest rate swaps \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 513,034		$ 515,646
Weighted Average Remaining Maturity (years)	5 years		5 years 3 months 18 days
Fair Value	$ (51,665)		$ (24,357)
Weighted-Average Rate	2.80%		2.80%
Cash collateral received			$ 81,300
Cash collateral pledged			42,300
Loans \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value	$ 44,586		21,440
Loans \| Interest rate swaps \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 424,834		$ 427,446
Weighted Average Remaining Maturity (years)	5 years 3 months 18 days		5 years 6 months
Fair Value	$ (44,872)		$ (21,551)
Weighted-Average Rate	2.86%		2.86%
Securities available-for-sale \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair Value	$ 6,790		$ 2,802
Securities available-for-sale \| Interest rate swaps \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 88,200		$ 88,200
Weighted Average Remaining Maturity (years)	3 years 10 months 24 days		4 years 1 month 6 days
Fair Value	$ (6,793)		$ (2,806)
Weighted-Average Rate	2.54%		2.54%
3-month LIBOR \| Interest rate swaps \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 110,000		$ 110,000
Weighted Average Remaining Maturity (years)	6 years 9 months 18 days		7 years 1 month 6 days
Fair Value	$ (17,509)		$ (8,390)
Derivative, variable interest rate	2.88%		2.88%
1-month LIBOR \| Interest rate swaps \| Derivatives designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Value	$ 100,000		$ 100,000
Weighted Average Remaining Maturity (years)	3 years 8 months 12 days		4 years
Fair Value	$ (9,378)		$ (5,040)
Derivative, variable interest rate	2.88%		2.88%

Average fixed interest rate related to the group of interest rate derivatives.

No definition available.

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ 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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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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- Definition

Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the period in the carrying value of derivative instruments reported as assets that are due to be disposed of within one year (or the normal operating cycle, if longer).

+ References

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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