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

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Financing: Long-Term Debt: Debt Transactions (Details) - USD ($) $ in Thousands	Aug. 26, 2021	Jun. 17, 2020	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less unamortized deferred financing costs			$ 26,878	$ 24,809
Senior Unsecured Notes Due 2024
Debt Instrument [Line Items]
Stated interest rate (percent)	1.037%
Debt Instrument, Term	3 years
Less unamortized deferred financing costs	$ 3,700
Corporate, Non-Segment \| Senior Unsecured Notes Due 2024
Debt Instrument [Line Items]
Proceeds from Issuance of Debt		$ 600,000
Corporate, Non-Segment \| Senior Unsecured Notes Due 2030
Debt Instrument [Line Items]
Proceeds from Issuance of Debt		$ 400,000
Stated interest rate (percent)		2.50%
Long-term Debt, Term		10 years