Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 16,121	$ 22,726
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on available for sale securities arising during the period	(20,822)	8,952
Change in minimum pension liability	912	0
Other comprehensive income (loss)	(19,910)	8,952
Comprehensive income (loss)	$ (3,789)	$ 31,678

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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