Income Taxes - Summary of Changes in Total Gross Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure [Abstract]
Beginning balance	$ 12,597	$ 11,398	$ 7,868
Increases related to tax positions taken during the prior period	796	968	256
Increases related to tax positions taken during the current period	3,420	2,697	4,032
Decreases related to tax positions taken during the prior period	(128)	(1,754)	(67)
Audit settlements	0	(403)	0
Lapse of statute of limitations	(2,170)	(309)	(691)
Ending balance	$ 14,515	$ 12,597	$ 11,398

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Amount of unrecognized tax benefits.

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
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Amount of decrease 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 settlements with taxing authorities.

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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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