Segment Information - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($) business	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) business segment	Jun. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reporting segments \| segment			2
Number businesses owned \| business	3		3
Revenue	$ 31,189	$ 26,854	$ 61,696	$ 52,040
Europe and Canada
Segment Reporting Information [Line Items]
Revenue	$ 1,300	$ 1,100	$ 2,600	$ 2,000

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration