Debt Instrument, Prepayment Penalty, Period Without Penalty

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- Definition

Derivative notional amount swapped

+ References

No definition available.

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- Definition

Extension Period

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- Definition

Number Of Extensions

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

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

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

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Debt - Summary (Details) $ in Thousands	6 Months Ended
Debt - Summary (Details) $ in Thousands	Jun. 30, 2020 USD ($) extention	Mar. 19, 2021	Sep. 29, 2020	Jul. 15, 2020	Apr. 17, 2020 USD ($) extention	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,603,092					$ 1,651,085
Unamortized debt issuance costs	(6,935)					(6,111)
Unamortized fair market value premium	34					39
Principal outstanding	$ 1,596,191					1,645,013
Weighted average interest rate	3.48%
Interest Rate Swaps
Debt Instrument [Line Items]
Derivative notional amount swapped	$ 775,000
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Stated interest rate	0.16225%
Term Loan \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
$300 Million Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, gross					$ 300,000
Number Of Extensions \| extention					2
Debt Instrument Term Extension Period	1 year
$300 Million Unsecured Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
$300 Million Unsecured Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.25%
Unsecured Credit Facility
Debt Instrument [Line Items]
Principal outstanding	$ 0					146,000
Debt Instrument, Maturity Date	Jan. 12, 2024
Maximum borrowing capacity	$ 500,000
Number Of Extensions \| extention	2
Debt Instrument Term Extension Period	6 months
Unsecured Credit Facility \| Prepaid Expenses and Other Assets
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (2,000)					(2,400)
Unsecured Credit Facility \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.90%
Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 975,000					875,000
Unamortized debt issuance costs	(4,718)					(3,625)
Principal outstanding	970,282					871,375
Unsecured Term Loans \| $150 Million Wells Fargo Unsecured Term Loan C
Debt Instrument [Line Items]
Long-term debt, gross	$ 0					150,000
Debt Instrument, Interest Rate, Effective Percentage	2.39%
Debt Instrument, Maturity Date	Sep. 29, 2020
Unsecured Term Loans \| $150 Million Wells Fargo Unsecured Term Loan B
Debt Instrument [Line Items]
Long-term debt, gross	$ 0					150,000
Debt Instrument, Interest Rate, Effective Percentage	3.05%
Debt Instrument, Maturity Date	Mar. 21, 2021
Unsecured Term Loans \| $150 Million Wells Fargo Unsecured Term Loan A
Debt Instrument [Line Items]
Long-term debt, gross	$ 150,000					150,000
Debt Instrument, Interest Rate, Effective Percentage	3.38%
Debt Instrument, Maturity Date	Mar. 31, 2022
Fixed Interest Rate (as a percent)	2.38%
Unsecured Term Loans \| $150 Million Unsecured Term Loan D [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 150,000					150,000
Debt Instrument, Interest Rate, Effective Percentage	2.85%
Debt Instrument, Maturity Date	Jan. 04, 2023
Fixed Interest Rate (as a percent)	1.85%
Unsecured Term Loans \| $300 Million Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 300,000					0
Debt Instrument, Interest Rate, Effective Percentage	3.31%
Debt Instrument, Maturity Date	Apr. 18, 2023
Fixed Interest Rate (as a percent)	1.72%
Unsecured Term Loans \| $300 Million Unsecured Term Loan [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Fixed Interest Rate (as a percent)		0.28%	1.17%
Unsecured Term Loans \| $175 Million Unsecured Term Loan E [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 175,000					175,000
Debt Instrument, Interest Rate, Effective Percentage	3.92%
Debt Instrument, Maturity Date	Jan. 15, 2024
Fixed Interest Rate (as a percent)	2.92%
Unsecured Term Loans \| $200 Million Unsecured Term Loan F [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 200,000					100,000
Debt Instrument, Maturity Date	Jan. 12, 2025
Unsecured Term Loans \| $200 Million Unsecured Term Loan F [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Fixed Interest Rate (as a percent)				2.11%
Unsecured Term Loans \| $200 Million Unsecured Term Loan F [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 575,000					575,000
Unamortized debt issuance costs	(1,918)					(2,117)
Principal outstanding	573,082					572,883
Unsecured Notes \| $100 Million Series F Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000					100,000
Stated interest rate	3.98%
Debt Instrument, Maturity Date	Jan. 05, 2023
Unsecured Notes \| $50 Million Series A Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,000					50,000
Stated interest rate	4.98%
Debt Instrument, Maturity Date	Oct. 01, 2024
Unsecured Notes \| $100 Million Series D Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000					100,000
Stated interest rate	4.32%
Debt Instrument, Maturity Date	Feb. 20, 2025
Unsecured Notes \| $75 Million Series G Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 75,000					75,000
Stated interest rate	4.10%
Debt Instrument, Maturity Date	Jun. 13, 2025
Unsecured Notes \| $50 Million Series B Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,000					50,000
Stated interest rate	4.98%
Debt Instrument, Maturity Date	Jul. 01, 2026
Unsecured Notes \| $80 Million Series C Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 80,000					80,000
Stated interest rate	4.42%
Debt Instrument, Maturity Date	Dec. 30, 2026
Unsecured Notes \| $20 Million Series E Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 20,000					20,000
Stated interest rate	4.42%
Debt Instrument, Maturity Date	Feb. 20, 2027
Unsecured Notes \| $100 Million Series H Unsecured Notes [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000					100,000
Stated interest rate	4.27%
Debt Instrument, Maturity Date	Jun. 13, 2028
Mortgage Loans Payable
Debt Instrument [Line Items]
Long-term debt, gross	$ 53,092					55,085
Unamortized debt issuance costs	(299)					(369)
Unamortized fair market value premium	34					39
Principal outstanding	52,827					54,755
Mortgage Loans Payable \| Wells Fargo Bank, National Association CMBS Loan
Debt Instrument [Line Items]
Long-term debt, gross	$ 49,473					51,406
Stated interest rate	4.31%
Debt Instrument, Maturity Date	Dec. 01, 2022
Penalty free prepayment period	3 months
Mortgage Loans Payable \| Thrivent Financial for Lutherans Due December 15, 2023 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 3,619					$ 3,679
Stated interest rate	4.78%
Debt Instrument, Maturity Date	Dec. 15, 2023
Penalty free prepayment period	3 months