CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income	$ 312,316	$ 309,155	$ 304,780	$ 958,326
Other comprehensive income (loss), net of tax
Change in fair value of derivatives, net of tax of $4,704, $22,050, $50,307 and $59,679, respectively	(15,750)	(73,822)	(168,421)	(199,795)
Derivative amounts reclassified to net income, net of tax of $(3,038), $2,673, $(3,360) and $8,654, respectively	5,361	(8,952)	11,210	(29,748)
Change in retirement and other postretirement benefit plan obligations, net of tax of $(1,064), $(737), $(3,192) and $(2,172), respectively	3,562	2,465	10,685	7,271
Other comprehensive income (loss) of unconsolidated affiliates, net of tax of $(332), $1,314, $3,015 and $3,164, respectively	1,112	(4,399)	(10,092)	(10,593)
Total other comprehensive loss, net of tax	(5,715)	(84,708)	(156,618)	(232,865)
Comprehensive income	$ 306,601	$ 224,447	$ 148,162	$ 725,461