CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 44,642	$ 29,383	$ 40,291	$ 87,976
Investments available-for-sale:
Net change in unrealized gains on investments available-for-sale	3,445	912	29,074	16,893
Related income tax expense	(909)	(239)	(7,424)	(4,418)
Net investment gains reclassified into earnings	(51)	(15)	(432)	(20)
Related income tax expense	13	4	110	5
Net effect on other comprehensive income for the period	2,498	662	21,328	12,460
Defined benefit pension plan:
Recognition of unrealized loss	219	264	656	794
Related income tax benefit	(48)	(69)	(159)	(208)
Net effect on other comprehensive income for the period	171	195	497	586
Total other comprehensive income	2,669	857	21,825	13,046
Comprehensive income	$ 47,311	$ 30,240	$ 62,116	$ 101,022

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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