Goodwill and Other Intangible Assets - Schedule of Carrying Value and Accumulated Amortization of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,552	$ 4,552
Accumulated Amortization	2,709	2,330
Customer list
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,012	4,012
Accumulated Amortization	2,379	2,048
Non-Compete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	270	270
Accumulated Amortization	146	103
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	270	270
Accumulated Amortization	$ 184	$ 179