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Note 14 - Debt (Details Textual) - USD ($) $ in Thousands |  |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 15, 2022 | Apr. 06, 2021 | Jun. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Feb. 03, 2022 | Feb. 02, 2022
Property, Plant and Equipment, Net, Total |  |  |  | $ 56,038,000 | $ 54,871,000 |  |  |
Debt Conversion, Converted Instrument, Amount |  |  |  | 0 | 100,000 | $ 250,000 |  |
Proceeds from Issuance of Commercial Paper |  |  |  | 3,200,000 |  |  |  |
Repayments of Commercial Paper |  |  |  | $ 3,400,000 |  |  |  |
Commercial Paper, Maturity Duration, Minimum (Day) |  |  |  | 7 days |  |  |  |
Commercial Paper Maturity Duration, Maximum (Year) |  |  |  | 88 years |  |  |  |
Commercial Paper |  |  |  | $ 200,000 | 400,000 |  |  |
Board of Directors Authorized Debt Issuance |  |  |  |  |  |  | $ 12,000,000 |
Previous Board of Directors Remaining Debt Issuance |  |  |  |  |  |  |  | $ 2,500,000
Board of Directors Remaining Debt Issuance |  |  |  | 6,600,000 |  |  |  |
Long-Term Debt, Gross |  |  |  | 35,101,000 |  |  |  |
Secured Debt [Member] |  |  |  |  |  |  |  |
Long-Term Debt, Gross |  |  |  | 100,000 | 300,000 |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity |  |  | $ 2,000,000 | 2,000,000 |  |  |  |
Long-Term Line of Credit, Total |  |  |  | 0 |  |  |  |
Allowable Debt Per Debt to Net Worth Coverage Ratio as Defined Facility |  |  |  | 46,900,000 |  |  |  |
Outstanding Debt as Defined by Facility |  |  |  | 35,100,000 |  |  |  |
Cross Default Provision as Defined By Facility |  |  |  | $ 150,000 |  |  |  |
Line of Credit Facility, Expiration Date |  |  | Jun. 08, 2023 | May 20, 2027 |  |  |  |
Conversion of Existing Notes [Member] |  |  |  |  |  |  |  |
Debt Conversion, Original Debt, Amount |  | $ 1,700,000 |  |  |  |  |  |
Payment of Financing and Stock Issuance Costs, Total |  | 257,000 |  |  |  |  |  |
Gain (Loss) on Extinguishment of Debt, Total |  | $ 0 |  |  |  |  |  |
Debt Conversion, Converted Instrument, Issuance Date |  | Apr. 06, 2021 |  |  |  |  |  |
Conversion of Existing Notes [Member] | Interest Expense [Member] |  |  |  |  |  |  |  |
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction |  | $ 13,000 |  |  |  |  |  |
Conversion of Existing Notes into New 2036 Notes [Member] |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Amount |  | $ 701,000 |  |  |  |  |  |
Debt Conversion, Converted Instrument, Rate |  | 2.891% |  |  |  |  |  |
Debt Conversion, Converted Instrument, Expiration or Due Date |  | Apr. 06, 2036 |  |  |  |  |  |
Conversion of Existing Notes into New 2071 Notes [Member] |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Amount |  | $ 1,000,000 |  |  |  |  |  |
Debt Conversion, Converted Instrument, Rate |  | 3.799% |  |  |  |  |  |
Debt Conversion, Converted Instrument, Expiration or Due Date |  | Apr. 06, 2071 |  |  |  |  |  |
Existing Notes [Member] |  |  |  |  |  |  |  |
Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total |  | $ 14,000 |  |  |  |  |  |
4.163% Notes, Due July 15, 2022 [Member] |  |  |  |  |  |  |  |
Debt Instrument, Repurchase Amount | $ 750,000 |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.163% |  |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed | 100.00% |  |  |  |  |  |  |
Debt Instrument, Repurchase Date | Apr. 15, 2022 |  |  |  |  |  |  |
4.950% Notes, Due September 9, 2052 [Member] |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 4.95% |  |  |  |
Debt Conversion, Converted Instrument, Expiration or Due Date |  |  |  | Sep. 09, 2052 |  |  |  |
Equipment [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Net, Total |  |  |  | $ 8,004,000 | 7,747,000 |  |  |
Asset Pledged as Collateral [Member] | Equipment [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Net, Total |  |  |  | $ 903,000 | $ 1,200,000 |  |  |

X
- Definition Total amount of debt (as defined in the facility) the debt-to-net-worth coverage ratio allowable under the revolving credit facility. + References No definition available. + Details
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- Definition Maximum duration of commercial paper maturities, in 'PnYnMnDTnHnMnS' format, for example, P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)(2)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: 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(19)(a)(3)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 + Details
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- Definition Expiration, mandatory redemption, or due date, in YYYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 + Details
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- Definition Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 + Details
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- Definition The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 3: 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)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 + Details
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- 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 https://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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Percentage of principal amount of debt redeemed. + References No definition available. + Details
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- Definition Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4297-108586 + Details
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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. + 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)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 + Details
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- Definition The cash outflow due to repaying amounts borrowed by issuing commercial paper. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585 + Details
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