Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended
	Aug. 16, 2017	Jun. 30, 2017	Jun. 30, 2016	Aug. 30, 2017	Aug. 10, 2017
Initial Public Offering
Repayments of long-term debt		$ 1.6	$ 2.3
Subsequent Event
Initial Public Offering
Repayments of long-term debt	$ 10.4
Payment of cash bonuses to certain employees	$ 0.7
Subsequent Event | TRA
Long-term Incentive Plan
Percentage of net cash savings, if any, in U.S. federal, state and local income tax and franchise tax that the Company is required to pay	85.00%
Percentage of net cash savings in U.S. federal, state and local income tax and franchise tax that the Company will retain	15.00%
Basis points (as a percent)	0.015%
Subsequent Event | Registration Rights Agreement
Registration Rights Agreement
Lock-up period	180 days
Period after closing of any underwritten offering of shares of Class A Common Stock in which the Company is not obligated to effect such a registration	90 days
Maximum value of registration of the Company's Class A common stock in which the Company is not obligated to effect any registration where such registration has been requested by holders of the Registrable Securities per the Registration Rights Agreement	$ 25.0
ESCO | Subsequent Event
Initial Public Offering
Cash consideration	$ 45.2
Class A Common Stock | Subsequent Event | LTIP
Long-term Incentive Plan
Common shares reserved for issuance					1,250,000
Class A Common Stock | ESCO | Subsequent Event
Initial Public Offering
Share price (in dollars per share)	$ 14.50
Senior Revolving Credit Facility | Subsequent Event
Revolving Credit Facility
Maximum borrowing capacity	$ 50.0
IPO | Class A Common Stock | Subsequent Event
Initial Public Offering
Stock issued (in shares)	5,862,069
Share price (in dollars per share)	$ 14.50
Gross proceeds from initial public offering	$ 85.0
Net proceeds from initial public offering	80.6
Underwriting discounts and commissions	4.4
Net proceeds from the initial public offering, after repayment of debt, funding of acquisition and other costs	26.3
Payment of offering related costs	$ 5.0
Over-Allotment Option | Class A Common Stock | Subsequent Event
Initial Public Offering
Number of shares available for purchase (in shares)				879,310