Fair Value Measurements (Carrying Amounts And Fair Values Of Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets:
Available-for-sale securities, carrying amount	$ 177.9	$ 170.1	$ 401.4
Available-for-sale securities, fair value	177.9	170.1
Liabilities:
Notes payable and current portion of long-term debt	2,221.0	2,594.8	845.2
Long-term debt	9,729.3	9,674.2	12,025.2
Short-term borrowings, fair value	2,221.0	2,594.8
Long-term borrowings, fair value	$ 10,170.4	10,095.1
Carrying Amount
Assets:
Available-for-sale securities, carrying amount		170.1	401.4
Liabilities:
Short-term borrowings, fair value		2,594.8	845.2
Long-term borrowings, fair value		9,674.2	12,025.2
Fair Value
Assets:
Available-for-sale securities, carrying amount		170.1	401.4
Liabilities:
Short-term borrowings, fair value		2,594.8	845.2
Long-term borrowings, fair value		$ 10,095.1	$ 12,471.4

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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-Publisher FASB
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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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