Retirement Benefits (Schedule of Components in Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Amounts recognized in the consolidated balance sheet consisted of:
Accrued retirement benefits	$ (3,698.2)	$ (2,802.2)
Defined Benefit Pension Plans
Amounts recognized in the consolidated balance sheet consisted of:
Other noncurrent assets	163.3	193.7
Other current liabilities	(65.3)	(64.2)
Accrued retirement benefits	(3,491.0)	(2,624.0)
Accumulated other comprehensive (income) loss before income taxes	6,195.0	5,036.3
Net amount recognized	2,802.0	2,541.8
Retiree Health Benefit Plans
Amounts recognized in the consolidated balance sheet consisted of:
Other noncurrent assets	1,381.3	1,043.6
Other current liabilities	(7.3)	(7.3)
Accrued retirement benefits	(207.2)	(178.2)
Accumulated other comprehensive (income) loss before income taxes	(348.0)	(159.3)
Net amount recognized	$ 818.8	$ 698.8

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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