Debt - Senior Unsecured Notes Issued (Detail) - USD ($) $ in Millions	2 Months Ended
Jun. 30, 2017	Sep. 30, 2016
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 18,563	$ 10,550
Issued Notes [Member] \| CR Bard Inc [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	9,675
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 2.133% Due June 6, 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 725
Debt instrument, interest rate	2.133%
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 2.404% Due June 5, 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,000
Debt instrument, interest rate	2.404%
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 2.894% Due June 6, 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,800
Debt instrument, interest rate	2.894%
Issued Notes [Member] \| CR Bard Inc [Member] \| Floating Rate Notes Due June 6, 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 500
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 3.363% Due June 6, 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,750
Debt instrument, interest rate	3.363%
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 3.700% Due June 6, 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 2,400
Debt instrument, interest rate	3.70%
Issued Notes [Member] \| CR Bard Inc [Member] \| Notes 4.669% Due June 6, 2047 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,500
Debt instrument, interest rate	4.669%
Exchanged Notes [Member] \| CR Bard Inc [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 1,150
Debt Conversion, Original Debt, Amount	1,031
Exchanged Notes [Member] \| CR Bard Inc [Member] \| Notes 4.400% due January 15, 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 500
Debt instrument, interest rate	4.40%
Debt Conversion, Original Debt, Amount	$ 428
Exchanged Notes [Member] \| CR Bard Inc [Member] \| Notes 3.000% due May 15, 2026 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 500
Debt instrument, interest rate	3.00%
Debt Conversion, Original Debt, Amount	$ 467
Exchanged Notes [Member] \| CR Bard Inc [Member] \| Notes 6.700% due December 1, 2026 [Member]
Debt Instrument [Line Items]
Long-term Debt, Excluding Current Maturities	$ 150
Debt instrument, interest rate	6.70%
Debt Conversion, Original Debt, Amount	$ 137

Principal amount of debt validly tendered and exchanged for new notes.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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