Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 48,559	$ 14,931
Unrealized gains and losses on available for sale debt securities:
Net unrealized (losses) gains arising during the period	(9,019)	16,746
Reclassification adjustment for gains included in net income	(171)	0
Total	(9,190)	16,746
Unrealized gains (losses) on derivatives	4,621	(5,713)
Amortization related to post-retirement obligations	(109)	84
Total other comprehensive (loss) income	(4,678)	11,117
Total comprehensive income	$ 43,881	$ 26,048

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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