Income Taxes - Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Unrecognized Tax Benefits [Roll Forward]
Balance at the beginning of the period	$ 10,942	$ 9,594	$ 11,727
Gross increase related to current fiscal year tax positions	1,153	1,027	1,168
Gross increase related to prior fiscal year tax positions	8,152	3,282	1,243
Settlements	(246)	(1,157)	(4,501)
Lapse of statute of limitations	(2,363)	(1,804)	(43)
Balance at the end of the period	$ 17,638	$ 10,942	$ 9,594

Unrecognized Tax Benefits [Roll Forward]

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- Definition

Amount of unrecognized tax benefits.

+ References

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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