Derivative Instruments and Hedging Activities - Value of Derivative Assets and Derivative Liabilities (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Other Assets
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	$ 88,135	$ 25,647
Other Assets \| Interest rate swap contracts—commercial loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	88,135	25,647
Notional amount, Derivatives (included in Other Assets)	918,481	740,762
Collateral posted, Derivatives (included in Other Assets)	0	0
Other Assets \| Interest rate lock commitments—mortgage loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	2,927	321
Notional amount, Derivatives (included in Other Assets)	86,674	9,829
Other Assets \| Forward sale contracts—mortgage loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Assets)	0	1
Notional amount, Derivatives (included in Other Assets)	0	12,750
Other Liabilities
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	87,989	25,615
Other Liabilities \| Interest rate swap contracts—commercial loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	87,989	25,615
Notional amount, Derivatives (included in Other Liabilities)	918,481	740,762
Collateral posted, Derivatives (included in Other Liabilities)	86,720	26,127
Other Liabilities \| Interest rate lock commitments—mortgage loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	0	0
Notional amount, Derivatives (included in Other Liabilities)	0	0
Other Liabilities \| Forward sale contracts—mortgage loans
Derivatives not Designated as Hedging Instruments
Fair value, Derivatives (included in Other Liabilities)	1,292	0
Notional amount, Derivatives (included in Other Liabilities)	$ 91,750	$ 0

Fair value of securities received as collateral against derivative assets.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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Nominal or face amount used to calculate payments on the derivative asset.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value of securities pledged as collateral against derivative liabilities.

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Nominal or face amount used to calculate payments on the derivative liability.

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