SUMMARY OF ACCOUNTING POLICIES - Concentration of Credit Risk (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Allowance for doubtful accounts
Balance at Beginning of Year	$ 91,396	$ 60,051	$ 57,302
Charged to Costs and Expenses	23,732	41,977	8,225
Deductions/ Write-Offs	(19,198)	(10,632)	(5,476)
Balance at End of Year	$ 95,930	$ 91,396	$ 60,051
Net sales \| Ten largest customers
Allowance for doubtful accounts
Concentration risk percentage (less than 10% for sales of services as a % of total sales)	39.00%	43.00%	41.00%
CTG \| Accounts Receivable \| Customer one
Allowance for doubtful accounts
Concentration risk percentage (less than 10% for sales of services as a % of total sales)	10.00%	11.00%	17.00%

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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Amount of direct write-downs of accounts receivable charged against the allowance.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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