Leases - Summary of Lease Cost (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2019
Lease cost:
Operating lease cost	$ 15,037	$ 30,380
Finance lease cost:
Depreciation of assets obtained under finance leases	1,553	4,017
Interest on lease liabilities	330	330
Short-term lease cost	1,406	2,017
Variable lease cost	2,043	3,722
Net lease cost	$ 20,369	$ 40,466

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of amortization expense attributable to right-of-use asset from finance lease.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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- Definition

Finance lease costs.

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