Contingencies and commitments Contingencies and commitments (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended											0 Months Ended	12 Months Ended	1 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 In re Amgen Inc. Securities Litigation [Member] complaints	Dec. 31, 2012 Larson v. Sharer, et al [Member] complaints	Dec. 31, 2012 Federal Derivative Ligiation [Member]	Dec. 31, 2012 Ramos v. Amgen Inc., et al. [Member] defendants	Dec. 31, 2012 Harris, et. al. v. Amgen Inc. [Member] plaintiffs	Sep. 01, 2009 Massachusetts Qui Tam Action [Member] states	May 07, 2009 Massachusetts Qui Tam Action [Member] states	Oct. 30, 2009 Amended Complaint, Massachusetts District Court [Member] states	Dec. 19, 2012 Original Qui Tam Actions [Member] actions	Dec. 31, 2012 Original Qui Tam Actions [Member] actions	Oct. 31, 2011 Additional Qui Tam [Member] actions	Dec. 19, 2012 Qui Tam Litigation, Civil Liability [Member]	Dec. 19, 2012 Qui Tam Litigation, Criminal Liability [Member]	Dec. 31, 2012 U.S. ex rel. May v. Amgen, et al. [Member] actions	Dec. 31, 2012 Settled Litigation Related to Sales and Marketing Practices [Member]	Dec. 19, 2012 Settled Litigation Related to Sales and Marketing Practices [Member] states	Dec. 31, 2012 U.S. District Court, Eastern District of New York [Member] Original Qui Tam Actions [Member] actions	Dec. 31, 2012 U.S. District Court, Western District of Washington [Member] Original Qui Tam Actions [Member] actions
Loss Contingencies [Line Items]
Number of stockholder complaints				6	3
Length of time Federal Derivative Litigation cases stayed after Amgen Inc. Securities Litigation						30 days
Number of defendants							4
Number of plaintiffs								2
Number of states with complaints										17	14
Number of states																			49
Number of pending claims																				8	1
Number of states with notice of intervention									14
Number of claims settled												9					2
Number of claims including pending and settled claims													10
Number of claims filed														1
Settlement agreement, consideration to resolve case															$ 612	$ 150
Compliance program and integrity obligations period																		5 years
Future rental commitments for abandoned leases	331
Rental expense on operating leases	117	131	115
Minimum contractual purchase commitments with third party manufacturers through 2014	39
Purchases under contractual purchase commitments	$ 123	$ 87	$ 68