BASIS OF PRESENTATION, CONSOLIDATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Immaterial Corrections to Prior Period Financial Information (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accrued wages, benefits and related taxes	$ 53,979	$ 67,334
Retained earnings	754,980	788,834
Total Bristow Group stockholders’ investment	1,113,477	1,170,891
Total stockholders’ investment	1,120,644	1,178,144
Previously Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Accrued wages, benefits and related taxes	49,030	62,385
Retained earnings	759,929	793,783
Total Bristow Group stockholders’ investment	1,118,426	1,175,840
Total stockholders’ investment	1,125,593	1,183,093
Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Long-term Debt, Current Maturities	(1,400,000)	(1,400,000)
Accrued wages, benefits and related taxes	4,949	4,949
Retained earnings	(4,949)	(4,949)
Total Bristow Group stockholders’ investment	(4,949)	(4,949)
Total stockholders’ investment	$ (4,949)	$ (4,949)

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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