Nature of Business and Summary of Significant Accounting Policies - Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016
Intangible Assets by Major Class [Line Items]
Finite-lived intangible assets, Cost	$ 16,040	$ 16,040
Finite-lived intangible assets, Accumulated amortization	(8,124)	(7,683)
Finite-lived intangible assets, Net book value	7,916	8,357
Customer relationships [Member]
Intangible Assets by Major Class [Line Items]
Finite-lived intangible assets, Cost	9,800	9,800
Finite-lived intangible assets, Accumulated amortization	(7,784)	(7,343)
Finite-lived intangible assets, Net book value	2,016	2,457
Non-compete agreement [Member]
Intangible Assets by Major Class [Line Items]
Finite-lived intangible assets, Cost	340	340
Finite-lived intangible assets, Accumulated amortization	(340)	(340)
Finite-lived intangible assets, Net book value	0	0
Trade name [Member]
Intangible Assets by Major Class [Line Items]
Finite-lived intangible assets, Cost	5,900	5,900
Finite-lived intangible assets, Accumulated amortization	0	0
Finite-lived intangible assets, Net book value	$ 5,900	$ 5,900