Note Payable (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Disclosure
Number of lines of credit	1
Aggregate borrowing capacity	$ 300
Accordian feature available amount	300
Note payable	$ 50	$ 54
Ratio of debt-to-total capital maximum	0.35
Minimum [Member]
Debt Disclosure
Line of credit, interest rate	0.99%	0.97%
Maximum
Debt Disclosure
Line of credit, interest rate	5.00%	1.03%

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Number Of Credit Facilities

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The effective interest rate during the reporting period.

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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- Definition

Indebtedness divided by net capital.

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