VARIABLE INTEREST ENTITIES - Balance Sheets of VIEs (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Mar. 31, 2019
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 153,885	$ 178,055
Restricted cash	38,910	0
Accounts receivable	228,793	216,791
Inventories	113,514	121,308
Prepaid expenses and other current assets	42,545	44,009
Total current assets	577,647	565,513
Investment in unconsolidated affiliates	109,986	118,203
Property and equipment, net	1,678,300	1,834,180
Right-of-use asset	331,743	0
Goodwill	0	18,436
Other assets	94,899	116,267
Total assets	2,792,575	2,652,599
Accounts payable	93,433	99,573
Accrued liabilities	232,589	150,648
Accrued interest	2,649	17,174
Short-term borrowings and current maturities of long-term debt	947,041	1,418,630
Total current liabilities	1,273,063	1,668,851
Long-term debt, less current maturities	75,611	8,223
Accrued pension liabilities	18,706	25,726
Other liabilities and deferred credits	7,905	26,229
Deferred taxes	59,862	111,203
Long-term operating lease liabilities	251,399	0
Total Liabilities	2,311,413	1,840,232
Bristow Aviation Holdings Limited
Variable Interest Entity [Line Items]
Cash and cash equivalents	98,991	83,499
Restricted cash	1,939	0
Accounts receivable	304,368	307,864
Inventories	77,856	85,977
Prepaid expenses and other current assets	31,275	36,646
Total current assets	514,429	513,986
Investment in unconsolidated affiliates	329	3,087
Property and equipment, net	261,390	281,944
Right-of-use asset	148,492	0
Goodwill	0	18,436
Other assets	164,103	229,902
Total assets	1,088,743	1,047,355
Accounts payable	479,989	442,187
Accrued liabilities	94,228	113,905
Accrued interest	2,702,306	2,399,704
Short-term borrowings and current maturities of long-term debt	77,763	85,287
Total current liabilities	3,354,286	3,041,083
Long-term debt, less current maturities	381,559	384,369
Accrued pension liabilities	18,706	25,726
Other liabilities and deferred credits	3,302	4,810
Deferred taxes	0	37,063
Long-term operating lease liabilities	34,852	0
Total Liabilities	$ 3,792,705	$ 3,493,051