Represents the debt instrument issuance price, expressed as a percentage of par value.

No definition available.

Name:	celg_DebtInstrumentIssuancePriceAsPercentageOfParValue
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Period Type:	duration

- Definition

Represents the price at which the entity may redeem all or a portion of the debt, as a percentage of the principal amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	celg_
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- Definition

Represents the price at which the entity may be required to repurchase the debt, as a percentage of the principal amount, if the entity undergoes a change in control.

+ References

No definition available.

+ Details

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e681-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20435746&loc=SL7669646-108580

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80784-113994

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Increase of additional borrowings on existing and new debt instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Increase in basis points of the stated interest rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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

+ Details

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- Definition

Gross amount, as of the balance sheet date, of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings in periods after one year or beyond the normal operating cycle, if longer, over the life of the long-term debt instruments to which such costs pertain.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 35

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=6439857&loc=d3e75592-113984

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 24

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Debt (Details) (USD $)	1 Months Ended
Debt (Details) (USD $)	Aug. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Carrying values of the entity's senior notes
Long-term debt		$ 4,228,300,000	$ 2,771,300,000
Senior notes, fair value		4,252,000,000
Interest rate swap contracts \| Designated as hedging instruments
Carrying values of the entity's senior notes
Gains recorded as reduction of debt		33,800,000
2.450% senior notes due 2015
Carrying values of the entity's senior notes
Long-term debt		515,700,000	520,100,000
Interest rate (as a percent)		2.45%
2012 issued notes \| Treasury rate locks
Carrying values of the entity's senior notes
Losses recorded to AOCI		31,400,000
1.900% senior notes due 2017
Carrying values of the entity's senior notes
Long-term debt		500,800,000	500,600,000
Interest rate (as a percent)		1.90%
3.250% senior notes due 2022
Carrying values of the entity's senior notes
Long-term debt		975,000,000	1,002,100,000
Interest rate (as a percent)		3.25%
2013 issued notes
Carrying values of the entity's senior notes
Debt Instrument, Increase, Additional Borrowings	1,500,000,000.000
Deferred Finance Costs, Noncurrent, Gross	12,500,000
Debt Instrument, Redemption Price as Percentage of Principal Amount	100.00%
Debt Instrument, Repurchase Price Due to Change in Control as Percentage of Principal Amount	101.00%
2.300% senior notes due 2018
Carrying values of the entity's senior notes
Long-term debt		400,100,000	0
Debt Instrument, Increase, Additional Borrowings	400,000,000.0
Interest rate (as a percent)	2.30%	2.30%
Issuance price as percentage of par value	99.792%
Debt Instrument, Interest Rate Increase	0.15
4.000% senior notes due 2023
Carrying values of the entity's senior notes
Long-term debt		698,100,000	0
Debt Instrument, Increase, Additional Borrowings	700,000,000.0
Interest rate (as a percent)	4.00%	4.00%
Issuance price as percentage of par value	99.452%
Debt Instrument, Interest Rate Increase	0.20
5.250% senior notes due 2043
Carrying values of the entity's senior notes
Long-term debt		396,600,000	0
Debt Instrument, Increase, Additional Borrowings	400,000,000.0
Interest rate (as a percent)	5.25%	5.25%
Issuance price as percentage of par value	99.147%
Debt Instrument, Interest Rate Increase	0.25
3.950% senior notes due 2020
Carrying values of the entity's senior notes
Long-term debt		492,400,000	499,000,000
Interest rate (as a percent)		3.95%
3.950% senior notes due 2020 \| Interest rate swap contracts \| Designated as hedging instruments
Carrying values of the entity's senior notes
Gains recorded as reduction of debt		14,700,000
5.700% senior notes due 2040
Carrying values of the entity's senior notes
Long-term debt		$ 249,600,000	$ 249,500,000
Interest rate (as a percent)		5.70%