Subsequent Events - Additional Information (Details) - Revolving Credit Facility [Member] - USD ($)	Jan. 10, 2018	Jan. 09, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Borrowing capacity			$ 800,000,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Maturity date of debt	2022-01	2018-11
Borrowing capacity	$ 1,000,000,000	$ 800,000,000
Decrease in facility fees	0.05%
Facility fees percentage	0.20%	0.25%
Subsequent Event [Member] | London Interbank Offered Rate (LIBOR) [Member]
Subsequent Event [Line Items]
Decrease in variable rate	0.10%
Debt instrument variable rate	1.15%	1.25%