Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net Income	$ 12,377	$ 85,520	$ 66,625	$ 136,774
Other Comprehensive Income:
Reclassification adjustment of derivatives and designated hedges into net income	(224)	(221)	(445)	(440)
Retirement liability adjustment	273	299	570	587
Total	49	78	125	147
Comprehensive Income	12,426	85,598	66,750	136,921
Comprehensive Income Attributable to Noncontrolling Interests	(1,009)	(1,711)	(2,635)	(3,299)
Comprehensive Income Adjusted for Noncontrolling Interests	$ 11,417	$ 83,887	$ 64,115	$ 133,622