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Derivative notional amount swapped

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Extension Period

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- Definition

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

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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.

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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.

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- Definition

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

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- Definition

Amount, after accumulated amortization, of debt discount (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.

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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.

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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.

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Debt - Summary (Details) $ in Thousands		6 Months Ended
Debt - Summary (Details) $ in Thousands	Feb. 25, 2021	Jun. 30, 2021 USD ($) extention	Apr. 18, 2023	Jul. 08, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Long-term debt, gross		$ 1,890,114			$ 1,709,102
Unamortized debt issuance costs		(5,849)			(5,841)
Debt Instrument, Unamortized Discount (Premium), Net		(134)			29
Principal outstanding		$ 1,884,131			1,703,290
Weighted average interest rate		2.99%
Interest Rate Swaps
Debt Instrument [Line Items]
Derivative notional amount swapped		$ 975,000
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Stated interest rate		0.1005%
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] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Unsecured Credit Facility
Debt Instrument [Line Items]
Principal outstanding		$ 284,000			107,000
Debt Instrument, Maturity Date		Jan. 12, 2024
Maximum borrowing capacity		$ 750,000
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		$ (2,200)			(1,600)
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			975,000
Unamortized debt issuance costs		(4,070)			(3,889)
Principal outstanding		970,930			971,111
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 \| $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			200,000
Debt Instrument, Interest Rate, Effective Percentage		3.11%
Debt Instrument, Maturity Date		Jan. 12, 2025
Fixed Interest Rate (as a percent)		2.11%
Unsecured Term Loans \| $300 Million Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, gross		$ 300,000			300,000
Debt Instrument, Interest Rate, Effective Percentage		1.28%
Debt Instrument, Maturity Date		Feb. 05, 2026
Fixed Interest Rate (as a percent)		0.28%
Unsecured Term Loans \| $300 Million Unsecured Term Loan [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Fixed Interest Rate (as a percent)			0.94%
Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross		$ 575,000			575,000
Unamortized debt issuance costs		(1,610)			(1,719)
Principal outstanding		573,390			573,281
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
Unsecured Notes \| $275 Million Series Unsecured Notes \| Subsequent Event [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 275,000
Stated interest rate				2.80%
Unsecured Notes \| $50 Million Unsecured Notes \| Subsequent Event [Member]
Debt Instrument [Line Items]
Long-term debt, gross				$ 50,000
Stated interest rate				2.95%
Mortgage Loans Payable
Debt Instrument [Line Items]
Long-term debt, gross		$ 56,114			52,102
Unamortized debt issuance costs		(169)			(233)
Debt Instrument, Unamortized Discount (Premium), Net		(134)			29
Principal outstanding		55,811			51,898
Mortgage Loans Payable \| Wells Fargo Bank, National Association CMBS Loan
Debt Instrument [Line Items]
Long-term debt, gross		$ 47,580			48,546
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		$ 3,494			3,556
Stated interest rate		4.78%
Debt Instrument, Maturity Date		Dec. 15, 2023
Penalty free prepayment period		3 months
Mortgage Loans Payable \| United of Omaha Life Insurance Company
Debt Instrument [Line Items]
Long-term debt, gross		$ 5,040			$ 0
Stated interest rate		3.71%
Debt Instrument, Maturity Date		Oct. 01, 2039