Long-Term Debt, Carrying Value and Fair Value of Debt Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 1,158,097	$ 1,166,934
Fair value	1,171,899	1,224,563
Unamortized debt discounts and issuance costs	(3,362)	(3,567)
Long-term Debt	1,154,735	1,163,367
Amount excluded on unamortized debt discounts and issuance costs	1,200	1,400
3.29% Senior Notes Due February, 27 2023 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	350,000	350,000
Fair value	$ 351,078	358,390
Interest rate	3.29%
Maturity Date	Feb. 27, 2023
4.2% Senior Notes Due March 1, 2028 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 500,000	500,000
Fair value	$ 512,724	549,239
Interest rate	4.20%
Maturity Date	Mar. 01, 2028
Credit line due September 30, 2021 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 0	0
Fair value	0	0
Bank Note Payable [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	3,097	1,934
Fair value	3,097	1,934
Revolving Credit Facility [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	0	0
Fair value	$ 0	$ 0
Debt Instrument, Basis Spread on Variable Rate	1.80%	1.50%
Maturity Date	Mar. 27, 2024
Term Loan [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 305,000	$ 315,000
Fair value	$ 305,000	$ 315,000
Maturity Date	Mar. 27, 2024

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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