Lease Obligations - Schedule of Maturity Analysis of Operating Lease Liabilities and Reconciliation of Undiscounted Cash Flows to Total Operating Lease Liability (Detail) $ in Thousands	Mar. 31, 2019 USD ($)
Leases [Abstract]
Due in one year or less	$ 660
Due after one year through two years	602
Due after two years through three years	437
Due after three years through four years	418
Due after four years through five years	252
Thereafter	1,881
Total undiscounted cash flows	4,250
Discount on cash flows	(901)
Total operating lease liability	$ 3,349