Leases - Schedule of Supplemental Cash Flow Information Related to Operating Leases (Detail)	3 Months Ended
	Jun. 30, 2019 USD ($)
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 3,746,000
Operating lease liabilities arising from obtaining ROU assets	101,026,000
Reductions to ROU assets resulting from reductions to operating lease liabilities	$ 1,267,000