Central Merger and Restructuring, Merger and Integration Costs - Additional Information (Details) - USD ($)					3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 27, 2016	Mar. 11, 2016	Feb. 19, 2016	Oct. 02, 2012	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2016	Sep. 30, 2012
Settlement reducing cash consideration
Accrual for restructuring costs					$ 4,100,000		$ 4,100,000			$ 5,400,000
Central Merger
Acquisitions
Interest acquired (as a percent)				100.00%
Common stock issued (in shares)				6,161,332
Assumption of debt, net of cash acquired				$ 217,700,000
Cash consideration payable in three years from the acquisition date, pursuant to the Merger Agreement and prior to Central Net Debt Working Capital and indemnification of certain defined adverse consequences, net	$ 27,000,000			27,000,000							$ 27,000,000
Maximum net debt working capital threshold amount				$ 275,000,000.0
Period after which contingent cash consideration to be paid				3 years
Threshold of net debt working capital, pursuant to the Merger Agreement											$ 285,000,000.0
Price of share at which former stockholders of acquiree can elect to pay applicable amount (in dollars per share)											$ 23.64
Minimum cash consideration to cover capped indemnities											$ 17,000,000.0
Settlement reducing cash consideration
Net debt working capital allowable claims			$ 1,500,000
Indemnification of certain defined adverse consequences incurred through September 30, 2015, net			1,500,000
Net debt working capital expense									$ 1,600,000
Net debt working capital expense, net of tax									$ 900,000
Net debt working capital disallowable claims			$ 1,600,000
Additional indemnity claims		$ 1,600,000					7,700,000
Indemnification of certain defined adverse consequences, net		$ 26,500,000
Reduction due to net debt working capital							6,600,000
Reduction due to indemnified claims							18,800,000
Change in amount of contingent consideration, liability	2,500,000
Contingent consideration, liability, current	24,500,000
Acquisition and integration related costs included in general and administrative expenses	800,000				1,000,000	$ 1,500,000	1,100,000	$ 3,300,000
Acquisition related costs, net of tax	$ 500,000
February 19, 2016 | Central Merger
Settlement reducing cash consideration
Net debt working capital at September 30, 2012 as defined in the Merger Agreement											291,600,000
Reduction of cash consideration payable											$ 6,600,000
Compensation and Payroll Withholdings
Settlement reducing cash consideration
Accrual for restructuring costs					3,000,000		3,000,000			3,600,000
Accrued Expenses
Settlement reducing cash consideration
Accrual for restructuring costs					300,000		300,000			300,000
Other long-term Liabilities
Settlement reducing cash consideration
Accrual for restructuring costs					$ 800,000		$ 800,000			$ 1,500,000