Revolving Credit Facility and Long-Term Debt - Narrative (Details) - USD ($) $ in Thousands		9 Months Ended
	Feb. 23, 2017	Sep. 30, 2017	Dec. 31, 2016	Jul. 06, 2016
Line of Credit Facility [Line Items]
2017 Debt facility	$ 7,000	$ 6,962	$ 0
Variable rate on 2017 debt facility		2.31611%
Outstanding borrowings		$ (278,462)
Credit Agreement
Line of Credit Facility [Line Items]
Outstanding borrowings		(271,500)
Maximum facility capital expenditures in the next 12 months		30,000
Remaining borrowing capacity on line of credit		$ 91,000
Debt subject to fixed interest rate			$ 45,000
London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Interest rate (percent)	1.00%
Variable Rate 1 | Credit Agreement
Line of Credit Facility [Line Items]
Variable interest rate percent		2.485%
Debt subject to variable interest rate		$ 84,500
Variable Rate 2 | Credit Agreement
Line of Credit Facility [Line Items]
Variable interest rate percent		2.48667%	2.77%
Debt subject to variable interest rate		$ 12,000	$ 150,000
Revolving Credit Facility | Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 275,000
Interest rate increase if in event of default		2.00%
Term Loan | Credit Agreement
Line of Credit Facility [Line Items]
Debt instrument, face amount				150,000
Bridge Loan | Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 25,000
Interest Rate Swap 1 | Credit Agreement
Line of Credit Facility [Line Items]
Fixed interest rate percent		2.2325%	2.9825%
Debt subject to fixed interest rate		$ 126,300	$ 130,000
Interest Rate Swap 2 | Credit Agreement
Line of Credit Facility [Line Items]
Fixed interest rate percent		2.365%	3.115%
Debt subject to fixed interest rate		$ 48,800
Minimum | Revolving Credit Facility | Credit Agreement
Line of Credit Facility [Line Items]
Commitment fee percentage		0.15%
Maximum | Revolving Credit Facility | Credit Agreement
Line of Credit Facility [Line Items]
Commitment fee percentage		0.40%