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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due beyond one year or the operating cycle, whichever is longer. Alternate captions include income taxes payable, noncurrent.

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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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Carrying value as of the balance sheet date of obligations incurred and payable for the acquisition of merchandise, materials, supplies and services pertaining to construction projects such as a housing development or factory expansion not classified as trade payables.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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Amount of investment in marketable security, classified as noncurrent.

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Amount of current assets classified as other.

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Amount of noncurrent assets classified as other.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for income and other taxes that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Other Consolidated Financial Statement Detail (Details Textual) $ in Millions, ₩ in Billions	3 Months Ended			12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 KRW (₩)	Feb. 29, 2012 USD ($)	Feb. 29, 2012 KRW (₩)
Business Acquisition [Line Items]
Other Liabilities, Noncurrent	$ 1,389.4	$ 1,628.7		$ 1,389.4	$ 1,628.7
Other Assets, Current	687.6	962.0		687.6	962.0
Increase to goodwill				1,080.1	1,267.3
Accrued construction in progress	125.2	159.7		125.2	159.7
TECFIDERA litigation settlement charge			$ 454.8	0.0	0.0	$ 454.8
Prepaid taxes	271.2	657.6		271.2	657.6
Investments and other assets	1,690.6	431.6		1,690.6	431.6
Accrued Income Taxes, Noncurrent	791.4	979.8		791.4	979.8
Solothurn
Business Acquisition [Line Items]
Accrued construction in progress	100.0	150.0		100.0	150.0
TECFIDERA \| Fumapharm AG
Business Acquisition [Line Items]
Increase to goodwill				1,200.0	1,500.0
TECFIDERA \| Fumapharm AG \| Twenty billion
Business Acquisition [Line Items]
Increase to goodwill	300.0
TECFIDERA \| Fumapharm AG \| Each additional one billion up to twenty billion
Business Acquisition [Line Items]
Cumulative sales level	20,000.0			20,000.0
TECFIDERA \| Fumapharm AG \| Fifteen billion
Business Acquisition [Line Items]
Cumulative sales level		15,000.0			15,000.0
TECFIDERA \| Fumapharm AG \| Sixteen billion
Business Acquisition [Line Items]
Increase to goodwill		600.0
Cumulative sales level		$ 16,000.0			$ 16,000.0
Ionis Pharmaceuticals
Business Acquisition [Line Items]
Investment in Ionis	563.8			563.8
Samsung Bioepis
Business Acquisition [Line Items]
Investment in Samsung Bioepis	$ 680.6			$ 680.6			₩ 759.5	$ 45.0	₩ 49.5