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Non-controlling Interest In Subsidiaries (Narrative) (Details) - Grand Bahama Power Company Limited [Member] - Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares [Member]	12 Months Ended
	Dec. 31, 2016 BSD / shares
Noncontrolling Interest [Line Items]
Preferred Stock, Redemption Price Per Share	BSD 1,000
Preferred Stock Per Cent Per Annum Fixed Cumulative Preferential Dividend	7.25%
Preferred Stock Per Cent Per Annum Fixed Cumulative Preferential Dividend, Next Three Years	8.50%
Preferred Stock Per Cent Per Annum Fixed Cumulative Preferential Dividend, Four Fiscal Years Thereafter	10.00%

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The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

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