Long-term Debt - Narrative (Details) - USD ($)	9 Months Ended
	Sep. 30, 2016	Jul. 06, 2016	Dec. 31, 2015
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 328,413,000
Credit Agreement
Line of Credit Facility [Line Items]
Outstanding borrowings	328,400,000
Remaining borrowing capacity on line of credit	$ 91,600,000
Variable Rate 1 | Credit Agreement
Line of Credit Facility [Line Items]
Variable interest rate percent	3.02%		1.74%
Debt subject to variable interest rate	$ 153,000,000		$ 65,800,000
Variable Rate 2 | Credit Agreement
Line of Credit Facility [Line Items]
Variable interest rate percent	5.00%		2.12%
Debt subject to variable interest rate	$ 400,000		$ 6,800,000
Revolving Credit Facility | Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 275,000,000
Interest rate increase if in event of default	2.00%
Swingline loan | Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity		25,000,000
Term Loan | Credit Agreement
Line of Credit Facility [Line Items]
Debt instrument, face amount		$ 150,000,000
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%
Interest Rate Swap 1 | Credit Agreement
Line of Credit Facility [Line Items]
Fixed interest rate percent	3.48%		2.48%
Debt subject to fixed interest rate	$ 131,300,000		$ 135,000,000
Interest Rate Swap 2 | Credit Agreement
Line of Credit Facility [Line Items]
Fixed interest rate percent	3.62%
Debt subject to fixed interest rate	$ 43,800,000