Discount rate used by lessee to determine present value of operating lease payments.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 3
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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 6
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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

The amount of right of way office lease expense.

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No definition available.

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Note 7 - Leases (Details Textual) - USD ($) $ in Millions	12 Months Ended
Note 7 - Leases (Details Textual) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 2.9
Lessee, Operating Lease, Liability, Payments, Due Year Two	0.3
Lessee, Operating Lease, Liability, Payments, Due Year Three	0.3
Lessee, Operating Lease, Liability, Payments, Due Year Four	0.5
Lessee, Operating Lease, Liability, Payments, Due Year Five	11.0
Right of Way Office Lease Expense	2.9	$ 3.4	$ 3.0
Short-term Lease, Cost	$ 22.2
Pipeline Right-of-way Contracts [Member]
Lessee, Operating Lease, Term of Contract	10 years
Lessee, Operating Lease, Renewal Term	10 years
Land Acquired in Mobile Bay Properties Acquisition [Member]
Lessee, Operating Lease, Renewal Term	5 years
Office Lease [Member]
Lessee, Operating Lease, Discount Rate	9.75%
Other Leases [Member]
Lessee, Operating Lease, Discount Rate	10.75%