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Capital Lease and Finance Obligations - Finance Obligations (Details) - FortisBC Energy - Natural gas distribution assets | 12 Months Ended
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Dec. 31, 2016
Capital Leased Assets [Line Items] |
Lease term (years) | 35 years
Contract termination option (years) | 17 years
Capital Leases | Minimum |
Capital Leased Assets [Line Items] |
Stated interest rate (percent) | 6.78%
Capital Leases | Maximum |
Capital Leased Assets [Line Items] |
Stated interest rate (percent) | 8.40%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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