Acquisitions - Quebec Inc (Details) - USD ($) $ in Thousands							12 Months Ended
	Sep. 15, 2017	Dec. 29, 2016	Dec. 09, 2016	Nov. 15, 2016	Nov. 02, 2016	Sep. 15, 2016	Dec. 31, 2016	Dec. 31, 2015
Acquisition
Acquisition-related contingent consideration							$ 1,493	$ 1,886
Quebec Inc.
Acquisition
Cash consideration, high end of range						$ 6,000
Cash consideration			$ 2,200		$ 2,200	$ 1,000
Closing date anniversary period for final contingent payment						12 months
Deferred stock consideration						$ 5,000
Equity consideration (in dollars)		$ 2,500		$ 2,500
Equity consideration (in shares)		194,054		201,353
Threshold number of specified business days for calculating stock consideration to be paid on specified days following the IPO						30 days
Deferred acquisition cash consideration						$ 5,000
Acquisition-date fair value of deferred cash consideration						$ 4,955
Cost of debt (as a percent)						7.80%
Discount						$ 45
Amortization of discount							13
Acquisition-date fair value of deferred stock consideration						4,445
Payment-date fair value of deferred stock consideration						$ 4,500
Discount of stock issuances (as a percent)						10.00%
Acquisition-related contingent consideration							$ 568
Quebec Inc. | Plan
Acquisition
Cash consideration	$ 600