Financial Instruments (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Unsecured Notes Two \| Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Drawn down amount under credit facility	$ 25,000,000
Unsecured notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt instrument, face amount	$ 375,000,000	$ 375,000,000

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

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Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant