Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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-Subparagraph (SX 210.5-02.19,20)
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Weighted average interest rate of long-term debt outstanding.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt (Summary of Long-term Debt) (Details) SEK in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 SEK	Dec. 31, 2017 USD ($)	Nov. 22, 2016 USD ($)	Jun. 09, 2016 USD ($)	Dec. 09, 2015 USD ($)	Dec. 24, 2013 USD ($)	Nov. 13, 2013	Jun. 18, 2013
Debt Instrument [Line Items]
Foreign currency translation		$ (0.4)
Debt, Current		223.3		$ 1,749.2
Unamortized Debt Issuance Expense		(92.2)		(71.9)
Long-term debt		15,202.9		12,865.3
Other Current Portion of Long-term Debt
Debt Instrument [Line Items]
Debt, Current		3.7		$ 2.4
2016 Term Loans
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate			2.944%	2.944%
Long-term debt		1,600.0		$ 100.0	$ 2,000.0
2018 Senior Notes (2.600%)
Debt Instrument [Line Items]
Debt, Current		0.0
Other Long Term Debt
Debt Instrument [Line Items]
Long-term debt		7.1		6.3
Senior Notes \| 2016 Senior Notes (1.350% coupon)
Debt Instrument [Line Items]
Debt, Current				649.9
Senior Notes \| 2018 Floating Rate Euro Notes
Debt Instrument [Line Items]
Foreign currency translation	$ (74.3)	5.3
Debt Instrument, Basis Spread on Variable Rate	0.87%
Debt, Current		0.0		600.2
Long-term debt		526.0		0.0
Senior Notes \| 2018 Senior Notes (2.600%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage										2.60%
Long-term debt		649.6		0.0
Senior Notes \| 2018 Senior Notes (3.000% coupon)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage							3.00%
Debt, Current		0.0		499.8
Long-term debt		499.6		0.0			$ 500.0
Senior Notes \| 2019 Senior Notes (2.500%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						2.50%
Long-term debt		999.1		999.5		$ 1,000.0
Senior Notes \| 2019 Senior Notes (2.550%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage									2.55%
Long-term debt		499.5		$ 499.7
Senior Notes \| 2020 Euro Senior Notes
Debt Instrument [Line Items]
Foreign currency translation	$ (111.4)	8.0
Debt instrument, interest rate, stated percentage			0.541%	0.541%	1.25%
Long-term debt		785.7		$ 897.6
Senior Notes \| 2020 Senior Notes (3.750% coupon)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage							3.75%
Long-term debt		499.9		499.9			$ 500.0
Senior Notes \| 2021 Senior Notes (3.150%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						3.15%
Long-term debt		2,247.7		2,248.2		$ 2,250.0
Senior Notes \| 2023 Senior Notes (3.125% coupon)
Debt Instrument [Line Items]
Aggregate principal amount								$ 750.0
Debt instrument, interest rate, stated percentage								3.125%
Long-term debt		775.3		765.4
Senior Notes \| 2023 Senior Notes (4.200%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage									4.20%
Long-term debt		498.6		498.8
Senior Notes \| 2024 Euro Senior Notes
Debt Instrument [Line Items]
Foreign currency translation	148.5	10.7
Debt instrument, interest rate, stated percentage					2.25%
Long-term debt		1,049.2		1,197.7
Senior Notes \| 2026 Senior Notes (3.950%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						3.95%
Long-term debt		2,233.5		2,235.0		$ 2,250.0
Senior Notes \| 2028 Euro Senior Notes
Debt Instrument [Line Items]
Foreign currency translation	(111.4)	8.0
Debt instrument, interest rate, stated percentage					3.125%
Long-term debt		781.1		892.0
Senior Notes \| 2043 Senior Notes (5.400%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						5.40%
Long-term debt		497.0		497.1
Senior Notes \| 2046 Senior Notes (5.250%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage						5.25%
Long-term debt		999.8		999.8		$ 1,000.0
Senior Notes \| 2020 Floating Rate Euro Notes [Domain]
Debt Instrument [Line Items]
Foreign currency translation	$ (45.7)
Debt Instrument, Basis Spread on Variable Rate	0.50%
Long-term debt		0.0		600.2
Bank Loan Obligations \| Meda Bank Loans
Debt Instrument [Line Items]
Debt, Current		219.6		0.0
Long-term debt \| SEK			SEK 2,000.0
Current portion of long-term debt
Debt Instrument [Line Items]
Unamortized Debt Issuance Expense		0.0		(3.1)
Medium-term Notes \| Meda Medium Term Notes
Debt Instrument [Line Items]
Long-term debt		$ 146.4		$ 0.0
2019 \| Medium-term Notes \| Meda Medium Term Notes
Debt Instrument [Line Items]
Long-term debt \| SEK			745.0
2018 \| Medium-term Notes \| Meda Medium Term Notes
Debt Instrument [Line Items]
Long-term debt \| SEK			SEK 588.0