Derivative Financial Instruments - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Interest rate swaps, notional amount	$ 1,481,109	$ 885,469
Interest rate swaps, net carrying value	(59,668)	(17,301)
Designated as Hedging Instrument [Member]
Interest rate swaps, notional amount	316,100	326,000
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Interest rate swaps, notional amount	1,021,500	541,500
Not Designated as Hedging Instrument [Member]
Interest rate swaps, notional amount	143,600	18,000
Interest Rate Swaps 1 [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Interest rate swaps, notional amount		139,960
Interest rate swaps, net carrying value		2,352
Interest Rate Swaps 1 [Member] | Not Designated as Hedging Instrument [Member]
Interest rate swaps, notional amount	62,779
Interest rate swaps, net carrying value	1,319
Interest Rate Swaps 2 [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Interest rate swaps, notional amount	316,051	186,009
Interest rate swaps, net carrying value	(28,689)	(7,769)
Interest Rate Swap [Member]
Interest rate swaps, notional amount	316,100	326,000
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Interest rate swaps, notional amount	1,021,500	541,500
Interest rate swaps, net carrying value	(25,300)	(8,530)
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Interest rate swaps, notional amount	80,779	18,000
Interest rate swaps, net carrying value	$ (6,998)	$ (3,354)