Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Derivative [Line Items]
Net unrealized gains (losses) arising during the period	$ 10,000,000	$ (135,978,000)
Income (loss) recognized	5,400,000	2,200,000
Cash flow hedge gain (loss) to be reclassified	(149,000,000)
Cash flow hedge termination gain	24,000,000
Right to reclaim cash collateral	86,500,000		$ 66,800,000
Obligation to return cash collateral	7,700,000		$ 7,700,000
Cash Flow Hedges
Derivative [Line Items]
Net unrealized gains (losses) arising during the period	$ 0	$ 0