CONDENSED CONSOLIDATED 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
Statement of Comprehensive Income [Abstract]
Net income	$ 11,453	$ 14,074	$ 83,018	$ 82,091
Other Comprehensive Income:
Change in unfunded benefit obligation for pension and other postretirement benefit plans - net of taxes of $73, $82, $146 and $166, respectively	273	308	549	623
Total other comprehensive income	273	308	549	623
Comprehensive income	$ 11,726	$ 14,382	$ 83,567	$ 82,714