The percentage of existing debt under IRSAs as it relates to a debt instrument covenant.

No definition available.

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Namespace Prefix:	nuvr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of periodic quarterly payments due.

+ References

No definition available.

+ Details

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Namespace Prefix:	nuvr_
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- Definition

Percentage of debt amount of the required periodic payments applied to principal.

+ References

No definition available.

+ Details

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Namespace Prefix:	nuvr_
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Balance Type:	na
Period Type:	duration

- Definition

The maximum amount of dividends available to be authorized contingent on the total leverage ratio.

+ References

No definition available.

+ Details

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- Definition

Information pertaining to the total leverage ratio required in related to contingencies involving dividend agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Information pertaining to the total leverage ratio required related to contingencies involving paying of unlimited dividends.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
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- Definition

Represents the total leverage ratio.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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-Topic 835
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-Paragraph 8
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-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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Balance Type:	na
Period Type:	instant

- 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

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
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-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
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-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Balance Type:	credit
Period Type:	instant

- 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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Note 6 - Secured Credit Facility (Details Textual)	3 Months Ended
Note 6 - Secured Credit Facility (Details Textual)	Mar. 31, 2025 USD ($)	Sep. 17, 2024 USD ($)	Jun. 21, 2024 USD ($)	Jun. 20, 2024 USD ($)	Aug. 29, 2019 USD ($)	Aug. 01, 2018 USD ($)
Dividends, Contingency, Maximum Amount Authorized from Total Leverage Ratio	$ 3,000,000
Total Leverage Ratio	5.01
Dividends Authorized at Three Million or Less [Member]
Dividends, Contingency, Total Leverage Ratio Required, Unlimited Dividends	3.5
Minimum [Member]
Debt Instrument, Covenants, Percentage of Debt Under IRSAs	35.00%
Maximum [Member]
Dividends, Contingency, Total Leverage Ratio Required	4.25
Total Leverage Ratio	6
First IRSA With CoBank [Member] \| Interest Rate Swap [Member]
Debt Instrument, Face Amount	$ 16,137,500					$ 16,137,500
Derivative, Notional Amount	$ 8,357,450
Debt, Weighted Average Interest Rate	6.71%
Second IRSA With CoBank [Member] \| Interest Rate Swap [Member]
Debt Instrument, Face Amount	$ 42,000,000				$ 42,000,000
Derivative, Notional Amount	$ 23,424,441
Debt, Weighted Average Interest Rate	5.04%
Third IRSA with CoBank [Member] \| Interest Rate Swap [Member]
Debt Instrument, Face Amount	$ 21,813,892	$ 21,813,892
Derivative, Notional Amount	$ 20,718,109
Debt, Weighted Average Interest Rate	7.77%
Delayed Draw Term Loan (DDTL) [Member] \| CoBank Credit Facility [Member]
Debt Instrument, Face Amount			$ 25,000,000
CoBank [Member]
Debt Instrument, Face Amount			180,000,000
Long-Term Debt	$ 91,600,000
Debt, Weighted Average Interest Rate	8.21%
CoBank [Member] \| Minimum [Member]
Debt Instrument, Covenants, Percentage of Debt Under IRSAs	35.00%
CoBank [Member] \| Revolving Credit Facility [Member]
Debt Instrument, Face Amount	$ 30,000,000
Line of Credit Facility, Maximum Borrowing Capacity			30,000,000	$ 40,000,000
Long-Term Line of Credit	$ 19,059,098
Line of Credit Facility, Commitment Fee Percentage	0.50%
CoBank [Member] \| Term A1 Loan [Member]
Debt Instrument, Basis Spread on Variable Rate	3.75%
CoBank [Member] \| Revolving Loan [Member]
Debt Instrument, Basis Spread on Variable Rate	3.75%
CoBank [Member] \| Term A1 Loan [Member]
Debt Instrument, Face Amount	$ 125,000,000		$ 125,000,000
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid	112,500,000
CoBank [Member] \| Term A1 Loan [Member] \| Debt Instrument, Redemption, Period One [Member]
Debt Instrument, Periodic Payment, Principal	781,250
CoBank [Member] \| Term A1 Loan [Member] \| Debt Instrument, Redemption, Period Two [Member]
Debt Instrument, Periodic Payment, Principal	1,562,500
CoBank [Member] \| Delayed Draw Term Loan (DDTL) [Member]
Debt Instrument, Face Amount	25,000,000
Long-Term Debt	0
Line of Credit Facility, Current Borrowing Capacity	$ 10,900,000
Line of Credit Facility, Commitment Fee Percentage	0.50%
CoBank [Member] \| Delayed Draw Term Loan (DDTL) [Member] \| Debt Instrument, Redemption, Period One [Member]
Debt Instrument, Number of Quarterly Periodic Payments	8
Debt Instrument, Principal, Periodic Payment, Percentage of Outstanding Loan Balance	0.625%
CoBank [Member] \| Delayed Draw Term Loan (DDTL) [Member] \| Debt Instrument, Redemption, Period Two [Member]
Debt Instrument, Number of Quarterly Periodic Payments	4
Debt Instrument, Principal, Periodic Payment, Percentage of Outstanding Loan Balance	1.25%