Derivatives, Hedging Activities and Balance Sheet Offsetting - Derivatives and Hedging Activities (Details) - USD ($)	Jun. 30, 2020	Feb. 29, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative assets, fair value	$ 14,391,000		$ 1,848,000
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, notional amount	55,927,000		16,734,000
Derivative assets, fair value	0		0
Derivative liabilities, fair value	4,066,000		1,113,000
Designated as Hedging Instrument \| Fair value hedges \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative, notional amount	25,927,000		16,734,000
Derivative assets, fair value	0		0
Derivative liabilities, fair value	3,106,000		1,113,000
Designated as Hedging Instrument \| Cash flow hedges \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative, notional amount	30,000,000	$ 30,000,000.0	0
Derivative assets, fair value	0		0
Derivative liabilities, fair value	960,000		0
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, notional amount	354,953,000		128,343,000
Derivative assets, fair value	14,391,000		1,848,000
Derivative liabilities, fair value	14,451,000		2,129,000
Not Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Derivative, notional amount	340,444,000		113,632,000
Derivative assets, fair value	14,388,000		1,824,000
Derivative liabilities, fair value	14,440,000		1,999,000
Not Designated as Hedging Instrument \| RPAs \| RPAs - protection sold
Derivatives, Fair Value [Line Items]
Derivative, notional amount	4,589,000		4,702,000
Derivative assets, fair value	3,000		24,000
Derivative liabilities, fair value	0		0
Not Designated as Hedging Instrument \| RPAs \| RPAs - protection purchased
Derivatives, Fair Value [Line Items]
Derivative, notional amount	9,920,000		10,009,000
Derivative assets, fair value	0		0
Derivative liabilities, fair value	$ 11,000		$ 130,000

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.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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