CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 9,987	$ 30,317
Investments available-for-sale:
Net change in unrealized gains on investments available-for-sale	14,263	8,814
Related income tax expense	(3,624)	(2,306)
Net investment gains reclassified into earnings	(169)	0
Related income tax expense	42	0
Net effect on other comprehensive income for the period	10,512	6,508
Defined benefit pension plan:
Recognition of unrealized loss	219	265
Related income tax expense	(55)	(69)
Net effect on other comprehensive income for the period	164	196
Total other comprehensive income	10,676	6,704
Comprehensive income	$ 20,663	$ 37,021

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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