v3.8.0.1

Fair Value Measurements - Summary of Fair Value Hierarchy for Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Jan. 01, 2017
--- | --- | ---
Assets: |  |
Estimated Fair Value | $ 920 | $ 824
Debt securities in government sponsored entities [Member] |  |
Assets: |  |
Estimated Fair Value | 67 | 34
Corporate debt securities [Member] |  |
Assets: |  |
Estimated Fair Value | 421 | 476
U.S. Treasury securities [Member] |  |
Assets: |  |
Estimated Fair Value | 432 | 314
Fair value, measurements, recurring [Member] |  |
Assets: |  |
Deferred compensation plan assets | 35 | 31
Total assets measured at fair value | 1,912 | 1,241
Liabilities: |  |
Acquisition-related contingent consideration liabilities |  | 4
Deferred compensation liability | 33 | 29
Total liabilities measured at fair value | 33 | 33
Fair value, measurements, recurring [Member] | Debt securities in government sponsored entities [Member] |  |
Assets: |  |
Estimated Fair Value | 67 | 34
Fair value, measurements, recurring [Member] | Corporate debt securities [Member] |  |
Assets: |  |
Estimated Fair Value | 421 | 476
Fair value, measurements, recurring [Member] | U.S. Treasury securities [Member] |  |
Assets: |  |
Estimated Fair Value | 432 | 314
Fair value, measurements, recurring [Member] | Money market funds (cash equivalent) [Member] |  |
Assets: |  |
Money market funds (cash equivalent) | 957 | 386
Fair value, measurements, recurring [Member] | Level 1 [Member] |  |
Assets: |  |
Total assets measured at fair value | 1,389 | 700
Fair value, measurements, recurring [Member] | Level 1 [Member] | U.S. Treasury securities [Member] |  |
Assets: |  |
Estimated Fair Value | 432 | 314
Fair value, measurements, recurring [Member] | Level 1 [Member] | Money market funds (cash equivalent) [Member] |  |
Assets: |  |
Money market funds (cash equivalent) | 957 | 386
Fair value, measurements, recurring [Member] | Level 2 [Member] |  |
Assets: |  |
Deferred compensation plan assets | 35 | 31
Total assets measured at fair value | 523 | 541
Liabilities: |  |
Deferred compensation liability | 33 | 29
Total liabilities measured at fair value | 33 | 29
Fair value, measurements, recurring [Member] | Level 2 [Member] | Debt securities in government sponsored entities [Member] |  |
Assets: |  |
Estimated Fair Value | 67 | 34
Fair value, measurements, recurring [Member] | Level 2 [Member] | Corporate debt securities [Member] |  |
Assets: |  |
Estimated Fair Value | $ 421 | 476
Fair value, measurements, recurring [Member] | Level 3 [Member] |  |
Liabilities: |  |
Acquisition-related contingent consideration liabilities |  | 4
Total liabilities measured at fair value |  | $ 4

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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