Segment Information - Reconciliation of Segment Income to Income before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting [Abstract]
Segment income	$ 167,917	$ 174,033	$ 447,420	$ 407,408
Interest and other debt expense	27,039	27,725	80,751	78,532
Income before income taxes	$ 140,878	$ 146,308	$ 366,669	$ 328,876