Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2020	Mar. 31, 2020
PROPERTY, PLANT AND EQUIPMENT, accumulated depreciation	$ 570,806	$ 529,068
INTANGIBLE ASSETS, accumulated amortization	670,383	631,449
Debt issuance costs, noncurrent, net	$ 24,022	$ 19,795
General partner, notional units outstanding (in units)	128,901	128,901
Limited partners, common units issued (in units)	128,771,715	128,771,715
Limited partners, common units outstanding (in units)	128,771,715	128,771,715
Class D Preferred Units
Preferred units dividend rate	9.00%	9.00%
Temporary equity, issued (in units)	600,000	600,000
Temporary equity, outstanding (in units)	600,000	600,000
Class B Perpetual Preferred Units
Preferred units, issued (in units)	12,585,642	12,585,642
Preferred units, outstanding (in units)	12,585,642	12,585,642
Class C Perpetual Preferred Units
Preferred units, issued (in units)	1,800,000	1,800,000
Preferred units, outstanding (in units)	1,800,000	1,800,000
General Partner
General partner interest	0.10%	0.10%
Limited Partner
Limited partner interest	99.90%	99.90%
Trade Accounts Receivable
Accounts receivable, allowance for expected credit loss	$ 3,674	$ 4,540

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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