STATEMENTS OF COMPREHENSIVE INCOME STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net income	$ 23,701	$ 20,253	$ 154,710	$ 145,922
Other comprehensive income (loss), net of tax
Change in pension and other postemployment benefit plan liability, net of tax of $(4), $(91), $(33) and $(273), respectively	12	300	111	899
Other comprehensive income, net of tax	12	300	111	899
Comprehensive income	$ 23,713	$ 20,553	$ 154,821	$ 146,821