Bank Note Payable and Term Note Payable (Details) - USD ($) $ in Thousands				6 Months Ended	12 Months Ended
	Jul. 22, 2016	Aug. 26, 2013	Sep. 27, 2012	Jun. 30, 2017	Dec. 31, 2016	Nov. 30, 2016	Jul. 21, 2016
Debt Instrument [Line Items]
Borrowings outstanding				$ 295,000	$ 280,000
BAML Revolver
Debt Instrument [Line Items]
Total available				500,000
Additional borrowing capacity allowed by exercising an accordion feature				350,000
Borrowings outstanding				$ 295,000	$ 280,000
Extension available on debt				12 months
Facility fee at period end (as a percent)				0.25%
Interest rate during period (as a percent)				2.32%	1.88%
Weighted average interest rate (as a percent)				2.14%	1.73%
BAML Revolver | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				1.25%
BAML Revolver | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				0.25%
BAML Term Loan
Debt Instrument [Line Items]
Principal amount of loan				$ 400,000
Amount drawn down			$ 400,000
Additional borrowing capacity allowed by exercising an accordion feature				$ 350,000
Effective interest rate (as a percent)				2.20%
BAML Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				1.45%
Fixed rate (as a percent)			0.75%
Future fixed interest rate	1.12%
BAML Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				0.45%
JPM Term Loan
Debt Instrument [Line Items]
Principal amount of loan						$ 150,000
Term of the borrowing				2 years
Interest rate during period (as a percent)				2.27%	1.99%
Weighted average interest rate (as a percent)				2.60%
JPM Term Loan | Eurodollar Rate
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				1.35%
JPM Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				0.35%
BMO Term Loan
Debt Instrument [Line Items]
Principal amount of loan				$ 220,000
Additional borrowing capacity allowed by exercising an accordion feature							$ 50,000
Effective interest rate (as a percent)				3.97%
BMO Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				1.65%
Fixed rate (as a percent)				2.32%
Term pursuant to interest rate swap agreement		7 years
BMO Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate at period end (as a percent)				0.65%