Other Comprehensive Income (Loss) Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017		Mar. 31, 2016		Dec. 31, 2016		Dec. 31, 2015	[5]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax		$ (74.5)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax		29.7		$ 27.7
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Arising During Period, before Tax	[1]	(21.1)		(15.4)
Accumulated other comprehensive loss		(5,064.3)				$ (5,274.0)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		8.8		115.6
Other comprehensive income (loss), net of tax	[2]	198.7		316.0
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax	[1]	76.8		73.5
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, before Tax		55.7		58.1
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Tax		(16.6)		(23.0)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax		39.1		35.1
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		(50.4)		5.5
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax		17.6		(1.9)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax		(32.8)		3.6
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax		18.1		(4.2)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, before Reclassification Adjustments, Tax		(8.5)		(25.7)
Other Comprehensive Income, Other, Net of Tax		2.5		76.9	[3]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax		(1.3)		(1.3)
Other Comprehensive Income (Loss), Tax		38.0		(3.5)
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Accumulated other comprehensive loss		(5,027.1)	[4]	(4,264.7)	[4]	(5,225.8)	[5]	$ (4,580.7)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		189.9		200.4
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		8.8		115.6
Other comprehensive income (loss), net of tax		198.7		316.0
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated other comprehensive loss		(208.4)	[4]	(216.1)	[4]	(210.9)	[5]	(218.5)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		0.0		0.0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		2.5		2.4
Other comprehensive income (loss), net of tax		2.5		2.4
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated other comprehensive loss		(3,349.4)	[4]	(2,981.1)	[4]	(3,371.6)	[5]	(3,012.1)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		(16.9)		(4.1)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		39.1		35.1
Other comprehensive income (loss), net of tax		22.2		31.0
Accumulated Net Investment Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member]
Accumulated other comprehensive loss		179.4	[4]	17.9	[4]	224.0	[5]	10.1
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		(11.8)		4.2
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		(32.8)		3.6
Other comprehensive income (loss), net of tax		(44.6)		7.8
Accumulated Translation Adjustment [Member]
Accumulated other comprehensive loss		(1,648.7)	[4]	(1,085.4)	[4]	(1,867.3)	[5]	$ (1,360.2)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		218.6		200.3
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment Realized upon Sale or Liquidation, Net of Tax		0.0		74.5
Other comprehensive income (loss), net of tax		218.6		$ 274.8
AOCI Attributable to Noncontrolling Interest [Member]
Accumulated other comprehensive loss		37.2				48.2
AOCI Attributable to Parent [Member]
Accumulated other comprehensive loss		$ 5,064.3				$ 5,274.0

[1] (1) These accumulated other comprehensive loss components are included in the computation of net periodic benefit (income) cost (see Note 9).

[2] (1) Other comprehensive income (loss) for the three months ended March 31, 2017 consisted of $209.7 million of other comprehensive income attributable to controlling interest and $(11.0) million of other comprehensive income (loss) attributable to non-controlling interest. Other comprehensive income (loss) for the three months ended March 31, 2016 attributable to non-controlling interest is immaterial.

[3] (2) Amount for the three months ended March 31, 2016 included primarily $74.5 million of foreign currency translation losses.

[4] (2) Accumulated other comprehensive loss as of March 31, 2017 consists of $5,064.3 million of accumulated other comprehensive loss attributable to controlling interest and $37.2 million of accumulated other comprehensive income attributable to non-controlling interest. The accumulated other comprehensive loss attributable to non-controlling interest as of March 31, 2016 is immaterial.

[5] (1) Accumulated other comprehensive loss as of January 1, 2017 consists of $5,274.0 million of accumulated other comprehensive loss attributable to controlling interest and $48.2 million of accumulated other comprehensive income attributable to non-controlling interest. The accumulated other comprehensive loss attributable to non-controlling interest as of January 1, 2016 is immaterial.