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Note 14 - Debt - Schedule of Debt (Details) (Parentheticals)	12 Months Ended
	Dec. 31, 2021
Notes Payable to Banks [Member]
Debt Instrument, Maturity Date	Apr. 06, 2071
Notes Payable to Banks [Member] | Minimum [Member]
Debt Instrument, Interest Rate	2.20%
Notes Payable to Banks [Member] | Maximum [Member]
Debt Instrument, Interest Rate	7.10%
Equipment Trust Certificate [Member]
Debt Instrument, Maturity Date	Jan. 02, 2031
Equipment Trust Certificate [Member] | Minimum [Member]
Debt Instrument, Interest Rate	2.60%
Equipment Trust Certificate [Member] | Maximum [Member]
Debt Instrument, Interest Rate	6.20%
Commercial Paper [Member]
Debt Instrument, Maturity Date	Jan. 26, 2022
Commercial Paper [Member] | Minimum [Member]
Debt Instrument, Interest Rate	0.20%
Commercial Paper [Member] | Maximum [Member]
Debt Instrument, Interest Rate	0.30%
Finance Lease [Member]
Debt Instrument, Maturity Date	Dec. 10, 2028
Finance Lease [Member] | Minimum [Member]
Debt Instrument, Interest Rate	3.10%
Finance Lease [Member] | Maximum [Member]
Debt Instrument, Interest Rate	8.00%
Loans Payable [Member]
Debt Instrument, Maturity Date	Aug. 31, 2022

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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X

- Definition

Latest date the outstanding debt instruments are required to be repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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