Schedule of Indebtedness Outstanding (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 1,611,662	$ 1,836,662
Debt Issuance Costs, Noncurrent, Net	359	406
Long-term Debt, Net of Debt Issuances Costs	1,611,303	1,836,256
Current installments of long-term debt	0	(225,000)
Long-term Debt	1,611,303	1,611,256
Line of Credit
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 600,000	600,000
Debt Instrument, Maturity Date	Dec. 30, 2026
Senior Notes - Series 2021-A due March 24, 2026
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 100,000	100,000
Debt Instrument, Maturity Date	Mar. 24, 2026
Senior Notes - Series 2021-B due March 24, 2031
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 400,000	400,000
Debt Instrument, Maturity Date	Mar. 24, 2031
Senior Notes - Series 2020-A due March 11, 2030
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 300,000	300,000
Debt Instrument, Maturity Date	Mar. 11, 2030
Senior Notes - Series 2015 A due February 15, 2022
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 0	225,000
Debt Instrument, Maturity Date	Feb. 15, 2022
Senior Notes - Series 2015-B due February 14, 2025
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 200,000	200,000
Debt Instrument, Maturity Date	Feb. 14, 2025
Other
Debt Instrument [Line Items]
Carrying amount of long-term debt	$ 11,662	$ 11,662

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