Variable Interest Entities Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Assets:
Current assets	$ 586,053	$ 498,101
TOTAL ASSETS	8,528,950	9,060,806	$ 8,777,361
Liabilities:
Current liabilities	500,351	528,939
TOTAL LIABILITIES	3,884,240	4,098,497
Variable Interest Entity, Primary Beneficiary
Assets:
TOTAL ASSETS	1,240,707	1,234,602
Liabilities:
TOTAL LIABILITIES	910,310	777,989
Cash | Variable Interest Entity, Primary Beneficiary
Assets:
Current assets	5,235	31
Receivables - Related Party | Variable Interest Entity, Primary Beneficiary
Assets:
Current assets	21,714	21,076
Receivables - Third Party | Variable Interest Entity, Primary Beneficiary
Assets:
Current assets	4,980	7,935
Other Current Assets | Variable Interest Entity, Primary Beneficiary
Assets:
Current assets	2,064	1,976
Property, Plant and Equipment, net | Variable Interest Entity, Primary Beneficiary
Assets:
Noncurrent assets	1,200,544	1,195,591
Operating Lease ROU Asset | Variable Interest Entity, Primary Beneficiary
Assets:
Noncurrent assets	3,225	4,731
Other Assets | Variable Interest Entity, Primary Beneficiary
Assets:
Noncurrent assets	2,945	3,262
Accounts Payable and Accrued Liabilities | Variable Interest Entity, Primary Beneficiary
Liabilities:
Current liabilities	32,223	67,290
Accounts Payable - Related Party | Variable Interest Entity, Primary Beneficiary
Liabilities:
Current liabilities	51,688	4,787
Revolving Credit Facility | Variable Interest Entity, Primary Beneficiary
Liabilities:
Current liabilities	347,000	311,750
Long-Term Debt | Variable Interest Entity, Primary Beneficiary
Liabilities:
Noncurrent liabilities	394,399	394,162
Long-Term Liabilities - Related Party | Variable Interest Entity, Primary Beneficiary
Liabilities:
Noncurrent liabilities	$ 85,000	$ 0