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

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- Definition

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

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- Definition

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

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Amount of the required periodic payments applied to interest.

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No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Long-Term Debt (Details) - USD ($)					12 Months Ended
Long-Term Debt (Details) - USD ($)	Jul. 19, 2023	Jan. 19, 2023	Feb. 03, 2022	Feb. 27, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Long-term Debt [Abstract]
Payments on long-term debt					$ 60,000,000	$ 150,000,000	$ 125,000,000
Senior Notes Due March 1, 2028 [Member]
Long-term Debt [Abstract]
Long term debt, face amount					$ 500,000,000
Debt instrument, interest rate, stated percentage					4.20%
Maturity Date					Mar. 01, 2028
Periodic payment, interest					$ 10,500,000
Senior Notes Series A Due February 27, 2020 [Member]
Long-term Debt [Abstract]
Payments on long-term debt				$ 150,000,000,000
Debt instrument, interest rate, stated percentage					2.72%
Senior Notes Series B Due February 27, 2023 [Member]
Long-term Debt [Abstract]
Long term debt, face amount					$ 350,000,000,000
Debt instrument, interest rate, stated percentage					3.29%
Maturity Date					Feb. 27, 2023
3.46 Series A Notes Due January 19, 2023 [Member]
Long-term Debt [Abstract]
Long term debt, face amount			$ 60,000,000
Debt instrument, interest rate, stated percentage			3.46%
Maturity Date			Jan. 19, 2033
3.51 Series B Notes Due January 19, 2023 [Member]
Long-term Debt [Abstract]
Long term debt, face amount			$ 240,000,000
Debt instrument, interest rate, stated percentage			3.51%
Maturity Date			Jan. 19, 2033
Periodic payment, interest	$ 5,250,000	$ 525,000
Line Of Credit [Member]
Long-term Debt [Abstract]
Maximum borrowing capacity					$ 10,000,000
Credit facility, expiration date					Jun. 30, 2022
Credit facility, amount outstanding					$ 1,299,000
Available borrowing capacity					8,701,000
Secured Debt [Member]
Long-term Debt [Abstract]
Short-term debt					$ 1,934,000	$ 40,000,000
Unsecured Debt [Member]
Long-term Debt [Abstract]
Long term debt, face amount			$ 300,000,000