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Notes Payable (Narrative) (Details) $ in Thousands			3 Months Ended	12 Months Ended
	Nov. 18, 2022 USD ($)	Mar. 08, 2017 USD ($)	Feb. 14, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)	Mar. 29, 2017 USD ($)
Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of debt		$ 320,000
Unsecured Notes Two | Revolving Credit Facility
Debt Instrument [Line Items]
Loan maximum borrowing capacity	$ 200,000					$ 75,000	$ 50,000
Undrawn portion of credit facility				$ 175,000
Drawn down amount under credit facility				25,000
Unamortized debt issuance cost				$ 900
Unsecured Notes Two | Revolving Credit Facility | Subsequent Event
Debt Instrument [Line Items]
Interest rate, effective percentage			5.68%
Drawn down amount under credit facility			$ 25,000
Unsecured Notes Two | Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Commitment fee on undrawn portion of facility	0.125%			0.15%
Unsecured Notes Two | Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Debt to total capital ratio				0.208
Commitment fee on undrawn portion of facility	0.225%
Unsecured Notes Two | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum
Debt Instrument [Line Items]
Debt to total capital ratio	0.30
Unsecured Notes Two | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Maximum
Debt Instrument [Line Items]
Debt to total capital ratio	0.20
Unsecured notes | Unsecured Notes One
Debt Instrument [Line Items]
Interest rate, stated percentage		4.40%
Debt issuance costs		$ 3,400
Discount percent		99.847%
Interest rate, effective percentage		4.45%
Unsecured notes | Unsecured Notes One | Notes payable
Debt Instrument [Line Items]
Unsecured debt		$ 375,000		$ 375,000	$ 375,000
Interest rate, stated percentage				4.40%
Unsecured notes | Unsecured Notes Two | Notes payable
Debt Instrument [Line Items]
Unsecured debt				$ 25,000	$ 0
Unsecured notes | Unsecured Notes Two | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum | Notes payable
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%
Unsecured notes | Unsecured Notes Two | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Maximum | Notes payable
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%

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