Fair Value Measurement (Schedule Of Assets And Liabilites Measured At Fair Value) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | $ 132 | $ 129 |
Money Market Funds [Member] | Cash Equivalents [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 32 | 266 |
Money Market Funds [Member] | Cash Equivalents [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Money Market Funds [Member] | Cash Equivalents [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 32 | 266 |
Money Market Funds [Member] | Cash Equivalents [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Commercial Paper [Member] | Cash Equivalents [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 17 | 70 |
Commercial Paper [Member] | Cash Equivalents [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Commercial Paper [Member] | Cash Equivalents [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 17 | 70 |
Commercial Paper [Member] | Cash Equivalents [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Commercial Paper [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 21 | 44 |
Commercial Paper [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Commercial Paper [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 21 | 44 |
Commercial Paper [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Corporate Bond Securities [Member] | Cash Equivalents [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 12 | 10 |
Corporate Bond Securities [Member] | Cash Equivalents [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Corporate Bond Securities [Member] | Cash Equivalents [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 12 | 10 |
Corporate Bond Securities [Member] | Cash Equivalents [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Corporate Bond Securities [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 375 | 113 |
Corporate Bond Securities [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Corporate Bond Securities [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 375 | 113 |
Corporate Bond Securities [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Mutual Funds [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 17 | 13 |
Mutual Funds [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 17 | 13 |
Mutual Funds [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Mutual Funds [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Municipal Bonds [Member] | Cash Equivalents [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 14 | 40 |
Municipal Bonds [Member] | Cash Equivalents [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Municipal Bonds [Member] | Cash Equivalents [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 14 | 40 |
Municipal Bonds [Member] | Cash Equivalents [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash equivalents | 0 | 0 |
Municipal Bonds [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 1 | 51 |
Municipal Bonds [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Municipal Bonds [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 1 | 51 |
Municipal Bonds [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Other Government Obligations [Member] | Cash Equivalents [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 14 | |
Other Government Obligations [Member] | Cash Equivalents [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | |
Other Government Obligations [Member] | Cash Equivalents [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 14 | |
Other Government Obligations [Member] | Cash Equivalents [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | |
Other Government Obligations [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 323 | 100 |
Other Government Obligations [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Other Government Obligations [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 323 | 100 |
Other Government Obligations [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Certificates of Deposit [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 11 | 5 |
Certificates of Deposit [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Certificates of Deposit [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 11 | 5 |
Certificates of Deposit [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Equity Securities [Member] | Marketable Securities [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 1 | 1 |
Equity Securities [Member] | Marketable Securities [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 1 | 1 |
Equity Securities [Member] | Marketable Securities [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Equity Securities [Member] | Marketable Securities [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Investments, Fair Value Disclosure | 0 | 0 |
Foreign Exchange Forward [Member] | Prepaid expenses and other current assets | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 65 | 97 |
Foreign Exchange Forward [Member] | Prepaid expenses and other current assets | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 0 | 0 |
Foreign Exchange Forward [Member] | Prepaid expenses and other current assets | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 65 | 97 |
Foreign Exchange Forward [Member] | Prepaid expenses and other current assets | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 0 | 0 |
Foreign Exchange Forward [Member] | Other assets | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 43 | 59 |
Foreign Exchange Forward [Member] | Other assets | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 0 | 0 |
Foreign Exchange Forward [Member] | Other assets | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 43 | 59 |
Foreign Exchange Forward [Member] | Other assets | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, asset | 0 | 0 |
Interest Rate Contract [Member] | Other assets | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 10 | 10 |
Interest Rate Contract [Member] | Other assets | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 0 | 0 |
Interest Rate Contract [Member] | Other assets | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 10 | 10 |
Interest Rate Contract [Member] | Other assets | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 0 | 0 |
Interest Rate Contract [Member] | Prepaid expenses and other current assets | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 2 | |
Interest Rate Contract [Member] | Prepaid expenses and other current assets | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 0 | |
Interest Rate Contract [Member] | Prepaid expenses and other current assets | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 2 | |
Interest Rate Contract [Member] | Prepaid expenses and other current assets | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Interest Rate Derivative Assets, at Fair Value | 0 | |
Foreign Exchange Forward [Member] | Other current liabilities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 14 | 12 |
Foreign Exchange Forward [Member] | Other current liabilities | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 0 | 0 |
Foreign Exchange Forward [Member] | Other current liabilities | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 14 | 12 |
Foreign Exchange Forward [Member] | Other current liabilities | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 0 | 0 |
Foreign Exchange Forward [Member] | Other liabilities | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 9 | 4 |
Foreign Exchange Forward [Member] | Other liabilities | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 0 | 0 |
Foreign Exchange Forward [Member] | Other liabilities | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 9 | 4 |
Foreign Exchange Forward [Member] | Other liabilities | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Foreign exchange forward contracts, liability | 0 | 0 |
Acquisition Related Contingent Consideration [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 157 | |
Acquisition Related Contingent Consideration [Member] | Current portion of contingent consideration | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 25 | 24 |
Acquisition Related Contingent Consideration [Member] | Current portion of contingent consideration | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 0 | 0 |
Acquisition Related Contingent Consideration [Member] | Current portion of contingent consideration | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 0 | 0 |
Acquisition Related Contingent Consideration [Member] | Current portion of contingent consideration | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 25 | 24 |
Acquisition Related Contingent Consideration [Member] | Contingent Consideration [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 132 | 129 |
Acquisition Related Contingent Consideration [Member] | Contingent Consideration [Member] | Level 1 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 0 | 0 |
Acquisition Related Contingent Consideration [Member] | Contingent Consideration [Member] | Level 2 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | 0 | 0 |
Acquisition Related Contingent Consideration [Member] | Contingent Consideration [Member] | Level 3 [Member] | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Contingent consideration | $ 132 | $ 129 |