Represents the leverage ratio as of the balance sheet date.

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Represents the amount of increase in the Line of Credit Accordion Feature borrowing capacity.

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Represents the percentage of Senior Unsecured Term Notes that will have right to require our Operating Partnership to Purchase per the Note Purchase Agreement.

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No definition available.

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Represents the percentage of Senior Unsecured Term Notes that holders may redeem for cash upon the occurrence of certain change of control events as defined in the Note Purchase Agreement.

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No definition available.

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Represents the percentage of Senior Unsecured Term Notes that may be prepaid by the Operating Partnership per the Note Purchase Agreement.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Debt - Unsecured Debt (Details) - USD ($) $ in Thousands			12 Months Ended
Debt - Unsecured Debt (Details) - USD ($) $ in Thousands	Nov. 08, 2019	Apr. 19, 2018	Dec. 31, 2019	Jul. 17, 2019	Apr. 17, 2019	Dec. 31, 2018	Apr. 20, 2017	Apr. 19, 2017	Jun. 15, 2016
Debt
Total principal outstanding			$ 1,487,500			$ 1,136,500
2020 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding						$ 150,000
Effective interest rate						3.37%
2021 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding						$ 100,000
Effective interest rate						3.90%
2022 Senior Unsecured Term Loan
Debt
Leverage ratio (as a percent)			29.00%
2022 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 200,000			$ 200,000
Effective interest rate			2.96%			3.65%
2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 150,000			$ 150,000
Effective interest rate			3.44%			4.01%
2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 350,000
Effective interest rate			2.81%
2023 Senior unsecured notes
Debt
Leverage ratio (as a percent)			29.00%
2023 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 150,000			$ 150,000
Effective interest rate			4.19%			4.19%
2024 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 175,000			$ 175,000
Effective interest rate			3.91%			3.91%
2026 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 200,000
Effective interest rate			4.52%
2029 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 200,000
Effective interest rate			4.31%
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 \| 2022 Senior Unsecured Term Loan \| LIBOR
Debt
Interest rate margin (as a percent)			1.40%
Operating partnership \| 2022 Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)			1.50%
Operating partnership \| 2022 Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)			2.10%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)			0.40%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)			1.00%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 200,000
Unsecured term loan								$ 100,000
Increase in accordion feature borrowing capacity								$ 300,000
Operating partnership \| 2024 Senior Unsecured Term Loan \| LIBOR
Debt
Interest rate margin (as a percent)			1.40%
Operating partnership \| 2024 Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)		1.40%
Operating partnership \| 2024 Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)		2.00%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding	150,000
Unsecured term loan	150,000
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding	350,000
Unsecured term loan	$ 350,000
Leverage ratio (as a percent)			29.00%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR
Debt
Interest rate margin (as a percent)			120.00%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)	120.00%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)	180.00%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)	20.00%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)	80.00%
Operating partnership \| 2023 Senior unsecured notes \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)	0.40%
Operating partnership \| 2023 Senior unsecured notes \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)	1.00%
Operating partnership \| 2023 Senior unsecured notes \| Senior Unsecured Notes \| Private Placement
Debt
Aggregate principal amount									$ 150,000
Stated interest rate									4.19%
Percentage of term notes that may be prepaid									100.00%
Percentage of term notes that holders have right to purchase in cash									100.00%
Percentage of term notes that holders may redeem for cash									100.00%
Operating partnership \| 2024 Senior unsecured notes \| Senior Unsecured Notes
Debt
Aggregate principal amount							$ 175,000
Stated interest rate							3.91%
Percentage of term notes that may be prepaid							100.00%
Percentage of term notes that holders have right to purchase in cash							100.00%
Percentage of term notes that holders may redeem for cash							100.00%
Operating partnership \| 2026 Senior unsecured notes \| Senior Unsecured Notes
Debt
Effective interest rate			4.52%		4.11%
Unsecured term loan					$ 200,000
Percentage of term notes that may be prepaid					100.00%
Percentage of term notes that holders have right to purchase in cash					100.00%
Percentage of term notes that holders may redeem for cash					100.00%
Operating partnership \| 2029 Senior unsecured notes \| Senior Unsecured Notes
Debt
Unsecured term loan				$ 75,000
Aggregate principal amount					$ 125,000
Percentage of term notes that may be prepaid					100.00%
Percentage of term notes that holders have right to purchase in cash					100.00%
Percentage of term notes that holders may redeem for cash					100.00%
Operating partnership \| 2029 Senior unsecured notes \| Senior Unsecured Notes \| Private Placement
Debt
Unsecured term loan					$ 200,000
Stated interest rate					4.31%