The percentage of the net property, plant and equipment accounted for under ASC 980, Regulated Operations.

No definition available.

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- Definition

Cap rate (rate of return and reimbursement of costs) on the previous year's revenue requirement.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(5))
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Jan. 01, 2019
Percentage of Net Property, Plant, and Equipment Accounted for Under ASC980	84.60%	84.30%
Revenue Requirement, Cap Interest Rate, Percent of Prior Year	95.00%
Contract with Customer, Liability, Total				$ 3,600,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total	$ 0
Operating Lease, Right-of-Use Asset	1,539,000	$ 1,146,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset					$ 1,073,919
Transport Services [Member]
Deferred Revenue, Total	2,000,000	2,100,000
Service, Other [Member]
Contract with Customer, Liability, Total	$ 188,000	$ 229,000
Revenue Benchmark [Member]
Concentration Risk, Percentage	100.00%	100.00%	100.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Interstate Access Services [Member]
Concentration Risk, Percentage	23.90%	23.30%	21.30%