STATEMENTS OF COMPREHENSIVE INCOME STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net income	$ 32,075	$ 30,093	$ 131,009	$ 125,668
Other comprehensive income (loss), net of tax
Change in pension and other postemployment benefit plan liability, net of tax of $(10), $(91), $(29) and $(182) respectively	30	299	99	599
Other comprehensive income, net of tax	30	299	99	599
Comprehensive income	$ 32,105	$ 30,392	$ 131,108	$ 126,267