Indebtedness (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2017	Jan. 29, 2015
Debt Instrument [Line Items]
Description of Lessee Leasing Arrangements, Capital Leases	capital lease obligations are primarily related to the procurement of hardware and health care devices
Line of Credit Facility, Maximum Borrowing Capacity	$ 100
Line of Credit Facility, Expiration Date	Oct. 29, 2020
Line of Credit Facility, Ability to Increase Borrowing Capacity, Maximum Amount	$ 200
Line of Credit Facility, Interest Rate Description	Interest is payable at a rate based on prime, LIBOR, or the U.S. federal funds rate, plus a spread that varies depending on the leverage ratios maintained.
Line of Credit Facility, Covenant Terms	The agreement provides certain restrictions on our ability to borrow, incur liens, sell assets and pay dividends and contains certain cash flow and liquidity covenants.
Letters of Credit Outstanding, Amount	$ 52
Line of Credit Facility, Remaining Borrowing Capacity	$ 48
Debt Instrument, Covenant Compliance	As of December 30, 2017, we were in compliance with all debt covenants
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 500
Debt Instrument, Restrictive Covenants	The Master Note Purchase Agreement contains certain leverage and interest coverage ratio covenants and provides certain restrictions on our ability to borrow, incur liens, sell assets, and other customary terms
Series 2015-A [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 225
Debt Instrument, Interest Rate, Stated Percentage		3.18%
Debt Instrument, Frequency of Periodic Payment	payable semiannually
Debt Instrument, Date of First Required Payment	Aug. 15, 2015
Debt Instrument, Maturity Date	Feb. 15, 2022
Series 2015-B [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 200
Debt Instrument, Interest Rate, Stated Percentage		3.58%
Debt Instrument, Maturity Date	Feb. 14, 2025
Series 2015-C [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 75
Debt Instrument, Frequency of Periodic Payment	payable quarterly
Debt Instrument, Date of First Required Payment	May 15, 2015
Debt Instrument, Maturity Date	Feb. 15, 2022
Other [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Sep. 30, 2025
London Interbank Offered Rate (LIBOR) [Member] \| Series 2015-C [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	Adjusted LIBOR Rate
Debt Instrument, Interest Rate During Period	2.42%

Line of Credit Facility, Ability to Increase Borrowing Capacity, Maximum Amount

No definition available.

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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The average effective interest rate during the reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Description of covenants that limit or prohibit certain actions or activities without the lender's prior consent within a specified period of time or until certain specified targets are achieved for example, reduction of the debt or an increase in net worth to a specified amount).

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- Definition

A general description of the lessee's leasing arrangements including, but not limited to, the following: a) the basis on which contingent rental payments are determined; (b) the existence and terms of renewal or purchase options and escalation clauses; (c) restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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