VARIABLE INTEREST ENTITIES AND OTHER INVESTMENTS IN SIGNIFICANT AFFILIATES, Statements of Operations of VIEs (Details) - USD ($) $ in Thousands  | 
1 Months Ended | 3 Months Ended | 5 Months Ended | 7 Months Ended | 12 Months Ended | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Oct. 31, 2020  | 
[1] | Sep. 30, 2020  | 
[2] | Jun. 30, 2020  | 
[3] | Mar. 31, 2020  | 
[4] | Dec. 31, 2019  | 
[5] | Sep. 30, 2019  | 
[6] | Jun. 30, 2019  | 
[7] | Mar. 31, 2019  | 
[8] | Mar. 31, 2020  | 
Oct. 31, 2019  | 
Dec. 31, 2020  | 
[1] | Mar. 31, 2019  | 
Mar. 31, 2018  | 
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| Variable Interest Entities and Other Investments in Significant Affiliates [Abstract] | ||||||||||||||||||||||||||||||||||||||
| Revenue | $ 105,827 | $ 318,220 | $ 333,176 | $ 284,839 | $ 329,858 | $ 349,343 | $ 366,668 | $ 323,793 | $ 485,763 | $ 757,223 | $ 200,924 | $ 1,369,662 | $ 1,433,975 | |||||||||||||||||||||||||
| Net loss | 139,076 | (836,206) | (336,138) | (197,109) | ||||||||||||||||||||||||||||||||||
| Bristow Aviation Holdings Limited | ||||||||||||||||||||||||||||||||||||||
| Variable Interest Entities and Other Investments in Significant Affiliates [Abstract] | ||||||||||||||||||||||||||||||||||||||
| Revenue | 413,885 | 663,047 | 1,221,344 | 1,241,223 | ||||||||||||||||||||||||||||||||||
| Operating loss | (14,083) | 45,505 | (41,148) | (65,254) | ||||||||||||||||||||||||||||||||||
| Net loss | $ (166,698) | $ (193,867) | $ (347,056) | $ (322,752) | ||||||||||||||||||||||||||||||||||
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