NOTES PAYABLE AND COMMERCIAL BANK FINANCING - Notes Payable and Finance Leases to Affiliates, Debt of VIEs and Guarantees of Third-Party Debt, and Bank Credit Agreement (Details) - USD ($) $ in Thousands	Apr. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Current portion of notes payable, finance leases and commercial bank financing		$ 42,193	$ 42,564
Notes payable, finance leases and commercial bank financing, less current portion		3,840,952	3,849,891
Consolidated total debt		3,883,100
Affiliated Entity
Debt Instrument [Line Items]
Current portion of notes payable, finance leases and commercial bank financing		1,900	1,900
Notes payable, finance leases and commercial bank financing, less current portion		10,200	10,600
Consolidated VIEs, aggregated
Debt Instrument [Line Items]
Notes payable, finance leases and commercial bank financing, less current portion		18,262	19,278
Consolidated total debt		23,400	24,400
Guarantee Obligations
Debt Instrument [Line Items]
Unconditional and irrevocably guaranteed debt		$ 74,600	$ 76,500
Subsequent Event | Term Loan | Term Loan A-2
Debt Instrument [Line Items]
Repayment of remaining principal balance	$ 91,500