Summary of Future Lease Commitments Related to Capital Lease Obligation (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Mar. 31, 2017
Leases [Abstract]
Fiscal 2018, remaining portion	$ 675
Fiscal 2019	1,349
Fiscal 2020	1,349
Fiscal 2021	1,373
Fiscal 2022	1,390
Thereafter	13,747
Total minimum lease payments	19,883
Less amounts representing interest	(3,922)
Total capital lease obligation	15,961
Less current capital lease obligation	(851)	$ (799)
Capital lease obligation, net of current portion	$ 15,110	$ 15,539

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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