UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 13,944	$ (1,716)	$ 27,443	$ 5,516
Available for sale securities
Unrealized holding gains (losses)	1,035	810	(1,852)	3,310
Less: reclassification adjustment for gains realized in net income		(57)		(57)
Total unrealized gains (losses) on available for sale securities	1,035	753	(1,852)	3,253
Interest rate swaps designated as cash flow hedges
Unrealized holding gains (losses)	3	633	(319)	4,960
Less: reclassification adjustment for gains realized in net income	(466)	(363)	(920)	(444)
Total unrealized gains (losses) on interest rate swaps	(463)	270	(1,239)	4,516
Defined benefit retirement plans
Change in retirement liabilities	7		15	(1)
Other comprehensive income (loss)	579	1,023	(3,076)	7,768
Comprehensive income (loss)	$ 14,523	$ (693)	$ 24,367	$ 13,284

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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