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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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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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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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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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			3 Months Ended
Debt - Unsecured Debt (Details) - USD ($) $ in Thousands	Apr. 15, 2020	Nov. 08, 2019	Mar. 31, 2020	Jul. 14, 2020	May 06, 2020	Dec. 31, 2019	Jul. 17, 2019	Apr. 17, 2019	Apr. 20, 2017	Apr. 19, 2017	Jun. 15, 2016
Debt
Total principal outstanding			$ 1,580,500			$ 1,487,500
Subsequent Event
Debt
Term of loan facility	7 years
Aggregate principal amount	$ 150,000			$ 50,000	$ 100,000
2022 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 200,000			$ 200,000
Effective interest rate			1.76%			2.96%
2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Unsecured term loan		$ 150,000
2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding			$ 350,000			$ 350,000
Effective interest rate			2.32%			2.81%
2023 Senior unsecured notes \| Senior Unsecured Term Loan
Debt
Effective interest rate			2.86%			3.44%
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
Debt
Effective interest rate			3.91%			3.91%
2024 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 175,000			$ 175,000
2026 Senior unsecured notes
Debt
Effective interest rate								4.52%
2026 Senior unsecured notes \| Senior Unsecured Term Loan
Debt
Unsecured term loan								$ 200,000
2026 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 200,000			200,000
Effective interest rate			4.52%
2029 Senior unsecured notes \| Senior Unsecured Term Loan
Debt
Unsecured term loan							$ 75,000
2029 Senior unsecured notes \| Senior Unsecured Notes
Debt
Total principal outstanding			$ 200,000			$ 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)			1.20%
Operating partnership \| 2022 Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)			1.20%
Operating partnership \| 2022 Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)			1.80%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)			0.20%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)			0.80%
Operating partnership \| 2022 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Unsecured term loan										$ 100,000
Increase in accordion feature borrowing capacity										300,000
Aggregate principal amount										$ 200,000
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan
Debt
Total principal outstanding		$ 150,000
Leverage ratio (as a percent)			31.20%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR
Debt
Interest rate margin (as a percent)			1.20%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)		1.20%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)		1.80%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)		20.00%
Operating partnership \| 2024 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)		0.80%
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)			31.20%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR
Debt
Interest rate margin (as a percent)			1.20%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Minimum
Debt
Interest rate margin (as a percent)		1.20%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| LIBOR \| Maximum
Debt
Interest rate margin (as a percent)		1.80%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Minimum
Debt
Interest rate margin (as a percent)		0.20%
Operating partnership \| 2025 Senior Unsecured Term Loan \| Senior Unsecured Term Loan \| Base Rate \| Maximum
Debt
Interest rate margin (as a percent)		0.80%
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 Term Loan
Debt
Unsecured term loan									$ 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 Term Loan
Debt
Stated interest rate								4.11%
Operating partnership \| 2026 Senior unsecured notes \| Senior Unsecured Notes
Debt
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 Term Loan
Debt
Aggregate principal amount								$ 125,000
Operating partnership \| 2029 Senior unsecured notes \| Senior Unsecured Term Loan \| Private Placement
Debt
Unsecured term loan								$ 200,000
Stated interest rate								4.31%
Operating partnership \| 2029 Senior unsecured notes \| Senior Unsecured Notes
Debt
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%