Derivative Instruments and Hedging Activities - Activity of Derivative Instruments Not Designated as Hedges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments and Hedging Activities Disclosures [Roll Forward]
Terminations	$ (495,500)
Trading | Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Roll Forward]
Beginning balance	$ 495,500	$ 495,500	$ 495,500
Additions		0	0
Terminations		(495,500)	0
Ending balance		$ 0	$ 495,500