Debt (Details) - Revolving Credit Facility and Term Loans - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Revolving credit facility outstanding balance		$ 302,100	$ 114,800
Outstanding balance		1,351,399
Unamortized debt issuance costs		(7,890)
Total term loans		570,670	421,444
Debt carrying value		$ 1,349,175	1,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date		May 18, 2019
Revolving credit facility outstanding balance	[1]	$ 302,100	$ 114,800
Interest rate	[2]	2.08%	1.98%
$425 Million Term Loans [Member]
Debt Instrument [Line Items]
Maturity date		May 18, 2020
Interest rate	[3]	2.84%	2.81%
Outstanding balance		$ 425,000	$ 425,000
$50 Million Term Loan [Member]
Debt Instrument [Line Items]
Maturity date		Apr. 08, 2021
Interest rate	[4]	2.54%
Outstanding balance		$ 50,000	0
$100 Million Term Loan [Member]
Debt Instrument [Line Items]
Maturity date		Apr. 08, 2023
Interest rate	[4]	3.13%
Outstanding balance		$ 100,000	0
Total Term Loans [Member]
Debt Instrument [Line Items]
Outstanding balance		575,000	425,000
Unamortized debt issuance costs		(4,330)	(3,556)
Total term loans		570,670	421,444
Total Revolving Credit Facility and Term Loans [Member]
Debt Instrument [Line Items]
Debt carrying value		$ 872,770	$ 536,244

[1] Unamortized debt issuance costs related to the revolving credit facility totaled approximately $3.1 million and $4.0 million as of September 30, 2016 and December 31, 2015, respectively, and are included in other assets, net in the Company's consolidated balance sheets.

[2] Annual variable interest rate at the balance sheet date.

[3] Effective annual interest rate which includes the effect of interest rate swaps on $322.5 million of the outstanding loan balance, resulting in an annual fixed interest rate of approximately 3.10% on this portion of the debt, subject to adjustment based on the Company's leverage ratio. See Note 6 for more information on the interest rate swap agreements. Remaining portion is variable rate debt.

[4] Annual fixed interest rate at the balance sheet date which includes the effect of an interest rate swap on the outstanding loan balance, subject to adjustment based on the Company's leverage ratio. See Note 6 for more information on the interest rate swap agreements.