FAIR VALUE OF FINANCIAL INSTRUMENTS (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Assets:
Restricted investment securities - landfill closure	$ 1,586		$ 1,248
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Assets:
Interest rate swaps		$ 0
Total asset fair value	1,586	1,248
Liabilities:
Interest rate swaps	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Landfills
Assets:
Restricted investment securities - landfill closure		1,248
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Assets:
Interest rate swaps		820
Total asset fair value	0	820
Liabilities:
Interest rate swaps	5,427	1,942
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Landfills
Assets:
Restricted investment securities - landfill closure		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Assets:
Interest rate swaps		0
Total asset fair value	0	0
Liabilities:
Interest rate swaps	$ 0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Landfills
Assets:
Restricted investment securities - landfill closure		$ 0