STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 59,326	$ 75,311
Other comprehensive (loss) income, net of tax
Change in unrealized holding (losses) gains on available-for-sale securities	(32,236)	5,478
Amortization of prior service costs and net actuarial loss on pension and other postretirement plans	2,660	1,232
Total other comprehensive (loss) income, net of tax	(29,576)	6,710
Comprehensive income	$ 29,750	$ 82,021

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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