Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Cash Flows [Abstract]
Net Cash Provided by Operating Activities	$ 306,957	$ 198,463
Cash Flows from Investing Activities:
Capital Expenditures	(121,473)	(105,380)
Investment in Contract Receivables	(5,704)	(6,166)
Proceeds from Contract Receivables	3,427	3,370
Investment in Affiliates	(20,769)	(196)
Return of Investment in Affiliates	4,000	0
Advances to Affiliates	(12,105)	0
Net Repayment of Notes Receivable - Affiliates	0	311
Divestiture Working Capital Settlement	0	(267)
Investment in Subsidiary, Net of Cash Acquired	(5,660)	0
Other	0	(4,000)
Net Cash Used in Investing Activities	(158,284)	(112,328)
Cash Flows from Financing Activities:
Net Repayments of Short-Term Credit Facilities	(243,300)	(425,100)
Proceeds from Issuance of Long-Term Debt	0	300,000
Principal Repayments of Long-Term Debt	(2,500)	(2,500)
Payments for Issuance of Long-Term Debt	0	(9,108)
Proceeds from Sale of Common Stock	100,380	42,272
Payments for the Issuance of Common Stock	0	(1,662)
Capital Distributions to Noncontrolling Interests in Subsidiaries	(130)	0
Capital Contributions of Noncontrolling Interests in Subsidiaries	43	0
Net Cash Used in Financing Activities	(145,507)	(96,098)
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	3,166	(9,963)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	29,440	41,831
Cash, Cash Equivalents and Restricted Cash at End of Period	$ 32,606	$ 31,868