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Debt - Summary of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Nov. 08, 2019	Apr. 17, 2019
Debt
Total principal outstanding	$ 1,580,500	$ 1,487,500
Unamortized deferred financing costs	(8,493)	(9,098)
Total debt	$ 1,572,007	$ 1,478,402
Revolving Credit Facility
Debt
Interest rate as of reporting date (as a percent)	2.45%	3.01%
Total principal outstanding	$ 155,500	$ 62,500
2022 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Interest rate as of reporting date (as a percent)	1.76%	2.96%
Total principal outstanding	$ 200,000	$ 200,000
Senior Unsecured Term Loan 2023 \| Senior Unsecured Term Loan
Debt
Total principal outstanding	$ 150,000	$ 150,000
2023 Senior unsecured notes \| Senior Unsecured Term Loan
Debt
Interest rate as of reporting date (as a percent)	2.86%	3.44%
2023 Senior unsecured notes \| Senior Unsecured Notes
Debt
Interest rate as of reporting date (as a percent)	4.19%	4.19%
Total principal outstanding	$ 150,000	$ 150,000
2024 Senior unsecured notes
Debt
Interest rate as of reporting date (as a percent)	3.91%	3.91%
2024 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding	$ 175,000	$ 175,000
2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Interest rate as of reporting date (as a percent)	2.32%	2.81%
Total principal outstanding	$ 350,000	$ 350,000
2026 Senior unsecured notes
Debt
Interest rate as of reporting date (as a percent)				4.52%
2026 Senior unsecured notes \| Senior Unsecured Notes
Debt
Interest rate as of reporting date (as a percent)	4.52%
Total principal outstanding	$ 200,000	200,000
2029 Senior unsecured notes \| Senior Unsecured Notes
Debt
Interest rate as of reporting date (as a percent)	4.31%
Total principal outstanding	$ 200,000	$ 200,000
Operating partnership \| 2020 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 150,000
Operating partnership \| 2021 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			100,000
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			150,000
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 350,000