Present value of lessee's discounted obligation for lease payments from operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of lessee's right to use underlying asset under operating lease.

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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)
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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ 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
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Preferred Stock, Shares Issued, Total			0
Operating Lease, Right-of-Use Asset	$ 81,455
Operating Lease, Liability, Total	$ 80,666
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset		$ 82,020
Operating Lease, Liability, Total		$ 82,020
Maximum [Member]
Property, Plant and Equipment, Useful Life	50 years
ACS Cable Systems LLC and Quintillion Holdings, LLC Joint Venture [Member]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	50.00%