Derivatives, Hedging Activities, and Other Financial Instruments - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Derivative [Line Items]
Collateral already posted, fair value	$ 57,500		$ 57,500		$ 13,700
Derivative liability	55,700		55,700		10,700
Interest Rate Swap
Derivative [Line Items]
Income (expense) in fair value adjustments	15	$ 407	364	$ 602
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, notional amount	$ 711,400		$ 711,400		$ 337,600