Merck & Co. (MRK) 10-Q 10 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Oct. 31, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'MRK	'
Entity Registrant Name	'Merck & Co. Inc.	'
Entity Central Index Key	'0000310158	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	2,850,873,371

INTERIM_CONSOLIDATED_STATEMENT

INTERIM CONSOLIDATED STATEMENT OF INCOME (USD $)	3 Months Ended		9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]	'	'	'	'
Sales	$10,557	$11,032	$31,755	$32,713
Costs, Expenses and Other	'	'	'	'
Materials and production	4,223	4,104	13,019	12,347
Marketing and administrative	2,975	2,803	8,681	8,929
Research and development	1,659	1,660	4,897	5,668
Restructuring costs	376	870	664	1,144
Equity income from affiliates	-24	-102	-241	-351
Other (income) expense, net	-142	172	-737	656
Total Costs, Expenses and Other	9,067	9,507	26,283	28,393
Income Before Taxes	1,490	1,525	5,472	4,320
Taxes on Income	648	375	865	618
Net Income	842	1,150	4,607	3,702
Less: Net (Loss) Income Attributable to Noncontrolling Interests	-53	26	3	79
Net Income Attributable to Merck & Co., Inc.	$895	$1,124	$4,604	$3,623
Basic Earnings per Common Share Attributable to Merck & Co., Inc. Common Shareholders, in dollars per share	$0.31	$0.38	$1.58	$1.22
Earnings per Common Share Assuming Dilution Attributable to Merck & Co., Inc. Common Shareholders, in dollars per share	$0.31	$0.38	$1.57	$1.20
Dividends Declared per Common Share, in dollars per share	$0.44	$0.43	$1.32	$1.29

INTERIM_CONSOLIDATED_STATEMENT1

INTERIM CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]	'	'	'	'
Net Income Attributable to Merck & Co., Inc.	$895	$1,124	$4,604	$3,623
Other Comprehensive Income (Loss) Net of Taxes:	'	'	'	'
Net unrealized gain (loss) on derivatives, net of reclassifications	254	-102	149	169
Net unrealized (loss) gain on investments, net of reclassifications	-29	43	33	-37
Benefit plan net (loss) gain and prior service (cost) credit, net of amortization	-463	49	-795	261
Cumulative translation adjustment	-316	72	-188	-409
Other comprehensive income (loss), net of taxes	-554	62	-801	-16
Comprehensive Income Attributable to Merck & Co., Inc.	$341	$1,186	$3,803	$3,607

CONSOLIDATED_BALANCE_SHEET

CONSOLIDATED BALANCE SHEET (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current Assets	'	'
Cash and cash equivalents	$11,370	$15,621
Short-term investments	2,977	1,865
Accounts receivable (net of allowance for doubtful accounts of $186 in 2014 and $146 in 2013) (excludes accounts receivable of $275 in 2014 and 2013 classified in Other assets - see Note 4)	6,515	7,184
Inventories (excludes inventories of $1,774 in 2014 and $1,704 in 2013 classified in Other assets - see Note 5)	5,819	6,226
Deferred income taxes and other current assets	4,740	4,763
Assets held for sale	3,302	26
Total current assets	34,723	35,685
Investments	13,492	9,770
Property, Plant and Equipment, at cost, net of accumulated depreciation of $18,761 in 2014 and $18,121 in 2013	13,438	14,973
Goodwill	13,171	12,301
Other Intangibles, Net	20,395	23,801
Other Assets	6,589	9,115
Total Assets	101,808	105,645
Current Liabilities	'	'
Loans payable and current portion of long-term debt	9,275	4,521
Trade accounts payable	2,279	2,274
Accrued and other current liabilities	9,808	9,501
Income taxes payable	2,467	251
Dividends payable	1,288	1,321
Liabilities held for sale	810	0
Total current liabilities	25,927	17,868
Long-Term Debt	18,566	20,539
Deferred Income Taxes	4,987	6,776
Other Noncurrent Liabilities	6,968	8,136
Merck & Co., Inc. Stockholders’ Equity	'	'
Common stock, $0.50 par value Authorized - 6,500,000,000 shares Issued - 3,577,103,522 shares in 2014 and 2013	1,788	1,788
Other paid-in capital	40,340	40,508
Retained earnings	39,989	39,257
Accumulated other comprehensive loss	-2,998	-2,197
Stockholders' equity before deduction for treasury stock	79,119	79,356
Less treasury stock, at cost: 716,260,636 shares in 2014 and 649,576,808 shares in 2013	33,895	29,591
Total Merck & Co., Inc. stockholders’ equity	45,224	49,765
Noncontrolling Interests	136	2,561
Total equity	45,360	52,326
Liabilities and Equity	$101,808	$105,645

CONSOLIDATED_BALANCE_SHEET_Par

CONSOLIDATED BALANCE SHEET (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Allowance for doubtful accounts	$186	$146
Accounts receivable classified in Other assets	275	275
Inventories classified in Other assets	1,774	1,704
Accumulated depreciation	$18,761	$18,121
Common stock, par value	$0.50	$0.50
Common stock, shares authorized	6,500,000,000	6,500,000,000
Common stock, shares issued	3,577,103,522	3,577,103,522
Treasury stock, shares	716,260,636	649,576,808

INTERIM_CONSOLIDATED_STATEMENT2

INTERIM CONSOLIDATED STATEMENT OF CASH FLOWS (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Cash Flows from Operating Activities	'	'
Net income	$4,607	$3,702
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	5,118	5,034
Intangible asset impairment charges	1,209	594
Gain on AstraZeneca option exercise	-741	0
Gain on divestiture of certain ophthalmic products	-396	0
Equity income from affiliates	-241	-351
Dividends and distributions from equity affiliates	132	178
Deferred income taxes	-1,773	-532
Share-based compensation	209	210
Other	-50	287
Net changes in assets and liabilities	950	-494
Net Cash Provided by Operating Activities	9,024	8,628
Cash Flows from Investing Activities	'	'
Capital expenditures	-827	-1,119
Purchases of securities and other investments	-16,231	-13,077
Proceeds from sales of securities and other investments	11,807	9,823
Acquisition of Idenix Pharmaceuticals, Inc., net of cash acquired	-3,700	0
Dispositions of businesses, net of cash divested	1,048	0
Proceeds from AstraZeneca option exercise	419	'
Other	-94	48
Net Cash Used in Investing Activities	-7,578	-4,325
Cash Flows from Financing Activities	'	'
Net change in short-term borrowings	3,077	151
Proceeds from issuance of debt	1	6,467
Payments on debt	-7	-515
Purchases of treasury stock	-6,083	-6,320
Dividends paid to stockholders	-3,911	-3,897
Proceeds from exercise of stock options	1,381	809
Other	72	-61
Net Cash Used in Financing Activities	-5,470	-3,366
Effect of Exchange Rate Changes on Cash and Cash Equivalents	-227	-298
Net (Decrease) Increase in Cash and Cash Equivalents	-4,251	639
Cash and Cash Equivalents at Beginning of Year	15,621	13,451
Cash and Cash Equivalents at End of Period	$11,370	$14,090

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	The accompanying unaudited interim consolidated financial statements of Merck & Co., Inc. (“Merck” or the “Company”) have been prepared pursuant to the rules and regulations for reporting on Form 10-Q. Accordingly, certain information and disclosures required by accounting principles generally accepted in the United States for complete consolidated financial statements are not included herein. These interim statements should be read in conjunction with the audited financial statements and notes thereto included in Merck’s Form 10-K filed on February 27, 2014.
	The results of operations of any interim period are not necessarily indicative of the results of operations for the full year. In the Company’s opinion, all adjustments necessary for a fair presentation of these interim statements have been included and are of a normal and recurring nature. Certain reclassifications have been made to prior year amounts to conform to the current presentation.
	Recently Issued Accounting Standards
	In May 2014, the Financial Accounting Standards Board issued amended accounting guidance on revenue recognition that will be applied to all contracts with customers. The objective of the new guidance is to improve comparability of revenue recognition practices across entities and to provide more useful information to users of financial statements through improved disclosure requirements. This guidance is effective for annual and interim periods beginning in 2017. Early adoption is not permitted. The Company is currently assessing the impact of adoption on its consolidated financial statements.

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2014
Restructuring and Related Activities [Abstract]	'
Restructuring	'
	Restructuring
	2013 Restructuring Program
	In October 2013, the Company announced a global restructuring program (the “2013 Restructuring Program”) as part of a global initiative to sharpen its commercial and research and development focus. As part of the program, the Company expects to reduce its total workforce by approximately 8,500 positions. These workforce reductions will primarily come from the elimination of positions in sales, administrative and headquarters organizations, as well as research and development. The Company will also reduce its global real estate footprint and continue to improve the efficiency of its manufacturing and supply network. The Company will continue to hire employees in strategic growth areas of the business as necessary.
	The Company recorded total pretax costs of $437 million and $826 million in the third quarter and first nine months of 2014, respectively, and $544 million in the third quarter and first nine months of 2013 related to this restructuring program. Since inception of the 2013 Restructuring Program through September 30, 2014, Merck has recorded total pretax accumulated costs of approximately $2.1 billion and eliminated approximately 4,965 positions comprised of employee separations, as well as the elimination of contractors and vacant positions. The actions under the 2013 Restructuring Program are expected to be substantially completed by the end of 2015 with the cumulative pretax costs estimated to be approximately $2.5 billion to $3.0 billion. The Company estimates that approximately two-thirds of the cumulative pretax costs will result in cash outlays, primarily related to employee separation expense. Approximately one-third of the cumulative pretax costs are non-cash, relating primarily to the accelerated depreciation of facilities to be closed or divested.
	Merger Restructuring Program
	In 2010, subsequent to the Merck and Schering-Plough Corporation (“Schering-Plough”) merger (the “Merger”), the Company commenced actions under a global restructuring program (the “Merger Restructuring Program”) designed to streamline the cost structure of the combined company. Further actions under this program were initiated in 2011. The actions under this program primarily reflect the elimination of positions in sales, administrative and headquarters organizations, as well as from the sale or closure of certain manufacturing and research and development sites and the consolidation of office facilities.
	On October 1, 2013, the Company sold its active pharmaceutical ingredient (“API”) manufacturing business, including the related manufacturing facility, in the Netherlands to Aspen Holdings (“Aspen”) as part of planned manufacturing facility rationalizations under the Merger Restructuring Program. Also in connection with the sale, Aspen acquired certain branded products from Merck, which transferred to Aspen effective December 31, 2013. Consideration for the transaction included cash of $705 million and notes receivable with a present value of $198 million at the time of disposition. The Company received $172 million of the cash portion of the consideration in the fourth quarter of 2013 and the remaining $533 million was received by the Company in January 2014.
	The Company recorded total pretax costs of $175 million and $423 million in the third quarter of 2014 and 2013, respectively, and $533 million and $841 million in the first nine months of 2014 and 2013, respectively, related to this restructuring program. Since inception of the Merger Restructuring Program through September 30, 2014, Merck has recorded total pretax accumulated costs of approximately $7.7 billion and eliminated approximately 27,855 positions comprised of employee separations, as well as the elimination of contractors and vacant positions. Approximately 4,445 position eliminations remain pending under this program as of September 30, 2014, which include the remaining actions under the 2008 Restructuring Program that are being reported as part of the Merger Restructuring Program as discussed below. The non-manufacturing related restructuring actions under the Merger Restructuring Program were substantially completed by the end of 2013. The remaining actions under this program relate to ongoing manufacturing facility rationalizations, which are expected to be substantially completed by 2016. The Company expects the estimated total cumulative pretax costs for this program to be approximately $7.9 billion to $8.2 billion. The Company estimates that approximately two-thirds of the cumulative pretax costs relate to cash outlays, primarily related to employee separation expense. Approximately one-third of the cumulative pretax costs are non-cash, relating primarily to the accelerated depreciation of facilities to be closed or divested.
	2008 Restructuring Program
	In 2008, Merck announced a global restructuring program (the “2008 Restructuring Program”) to reduce its cost structure, increase efficiency, and enhance competitiveness. Pretax costs of $54 million were recorded in the first nine months of 2013 related to the 2008 Restructuring Program. Effective July 1, 2013, any remaining activities under the 2008 Restructuring Program are being accounted for as part of the Merger Restructuring Program.
	For segment reporting, restructuring charges are unallocated expenses.
	The following tables summarize the charges related to restructuring program activities by type of cost:
		Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
	($ in millions)	Separation			Accelerated			Other			Total			Separation		Accelerated			Other			Total
		Costs			Depreciation									Costs		Depreciation
	2013 Restructuring Program
	Materials and production	$	—		$	5		$	—		$	5		$	—	$	189		$	17		$	206
	Marketing and administrative	—			45			—			45			—		92			—			92
	Research and development	—			75			6			81			—		160			14			174
	Restructuring costs	310			—			(4		)	306			387		—			(33		)	354
		310			125			2			437			387		441			(2		)	826
	Merger Restructuring Program
	Materials and production	—			67			15			82			—		219			(48		)	171
	Marketing and administrative	—			29			(6		)	23			—		54			(3		)	51
	Research and development	—			—			—			—			—		—			1			1
	Restructuring costs	5			—			65			70			104		—			206			310
		5			96			74			175			104		273			156			533
		$	315		$	221		$	76		$	612		$	491	$	714		$	154		$	1,359
		Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
	($ in millions)	Separation			Accelerated			Other			Total			Separation		Accelerated			Other			Total
		Costs			Depreciation									Costs		Depreciation
	2013 Restructuring Program
	Materials and production	$	—		$	20		$	—		$	20		$	—	$	20		$	—		$	20
	Marketing and administrative	—			15			—			15			—		15			—			15
	Research and development	—			8			—			8			—		8			—			8
	Restructuring costs	501			—			—			501			501		—			—			501
		501			43			—			544			501		43			—			544
	Merger Restructuring Program
	Materials and production	—			30			7			37			—		91			78			169
	Marketing and administrative	—			20			(4		)	16			—		44			1			45
	Research and development	—			1			—			1			—		30			—			30
	Restructuring costs	241			—			128			369			435		—			162			597
		241			51			131			423			435		165			241			841
	2008 Restructuring Program
	Materials and production	—			—			—			—			—		(2		)	6			4
	Marketing and administrative	—			—			—			—			—		4			—			4
	Restructuring costs	—			—			—			—			34		—			12			46
		—			—			—			—			34		2			18			54
		$	742		$	94		$	131		$	967		$	970	$	210		$	259		$	1,439
	Separation costs are associated with actual headcount reductions, as well as those headcount reductions which were probable and could be reasonably estimated. In the third quarter and first nine months of 2014, approximately 830 positions and 3,425 positions, respectively, were eliminated under the 2013 Restructuring Program. In the third quarter of 2014 and 2013, approximately 185 positions and 1,070 positions, respectively, and in the first nine months of 2014 and 2013, approximately 975 positions and 2,475 positions, respectively, were eliminated under the Merger Restructuring Program. In addition, approximately 55 positions were eliminated in the first nine months of 2013 under the 2008 Restructuring Program. These position eliminations were comprised of actual headcount reductions and the elimination of contractors and vacant positions.
	Accelerated depreciation costs primarily relate to manufacturing, research and administrative facilities and equipment to be sold or closed as part of the programs. Accelerated depreciation costs represent the difference between the depreciation expense to be recognized over the revised useful life of the site, based upon the anticipated date the site will be closed or divested, and depreciation expense as determined utilizing the useful life prior to the restructuring actions. All of the sites have and will continue to operate up through the respective closure dates and, since future undiscounted cash flows were sufficient to recover the respective book values, Merck was required to accelerate depreciation of the site assets rather than record an impairment charge. Anticipated site closure dates, particularly related to manufacturing locations, have been and may continue to be adjusted to reflect changes resulting from regulatory or other factors.
	Other activity in 2014 and 2013 includes pretax gains and losses resulting from sales of facilities and related assets, as well as asset abandonment, shut-down and other related costs. Additionally, other activity includes certain employee-related costs associated with pension and other postretirement benefit plans (see Note 12) and share-based compensation.
	Adjustments to previously recorded amounts were not material in any period.
	The following table summarizes the charges and spending relating to restructuring activities by program for the nine months ended September 30, 2014:
	($ in millions)	Separation			Accelerated			Other			Total
		Costs			Depreciation
	2013 Restructuring Program
	Restructuring reserves January 1, 2014	$	745		$	—		$	23		$	768
	Expense	387			441			(2		)	826
	(Payments) receipts, net	(596		)	—			(46		)	(642		)
	Non-cash activity	—			(441		)	43			(398		)
	Restructuring reserves September 30, 2014 (1)	$	536		$	—		$	18		$	554
	Merger Restructuring Program
Restructuring reserves January 1, 2014	$	725		$	—		$	12		$	737
Expense	104			273			156			533
(Payments) receipts, net	(237		)	—			(171		)	(408		)
Non-cash activity	—			(273		)	10			(263		)
Restructuring reserves September 30, 2014 (1)	$	592		$	—		$	7		$	599
(1)	The cash outlays associated with the 2013 Restructuring Program are expected to be substantially completed by the end of 2015. The non-manufacturing cash outlays associated with the Merger Restructuring Program were substantially completed by the end of 2013; the remaining cash outlays are expected to be substantially completed by 2016.

Acquisitions_Divestitures_Rese

Acquisitions, Divestitures, Research Collaborations and License Agreements	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Acquisitions, Divestitures, Research Collaborations and License Agreements	'
	Acquisitions, Divestitures, Research Collaborations and License Agreements
	The Company continues its strategy of establishing external alliances to complement its substantial internal research capabilities, including research collaborations, licensing preclinical and clinical compounds to drive both near- and long-term growth. The Company supplements its internal research with a licensing and external alliance strategy focused on the entire spectrum of collaborations from early research to late-stage compounds, as well as access to new technologies. These arrangements often include upfront payments, as well as expense reimbursements or payments to the third party, and milestone, royalty or profit share payments, contingent upon the occurrence of certain future events linked to the success of the asset in development. The Company also reviews its pipeline to examine candidates which may provide more value through out-licensing and, as part of its portfolio assessment process, may also divest certain products.
	In August 2014, Merck completed the acquisition of Idenix Pharmaceuticals, Inc. (“Idenix”) for approximately $3.9 billion in cash. Idenix is a biopharmaceutical company engaged in the discovery and development of medicines for the treatment of human viral diseases, whose primary focus is on the development of next-generation oral antiviral therapeutics to treat hepatitis C virus (“HCV”) infection. The transaction was accounted for as an acquisition of a business; accordingly, the assets acquired and liabilities assumed were recorded at their respective fair values as of the acquisition date. The determination of fair value requires management to make significant estimates and assumptions. Merck recognized an intangible asset for in-process research and development (“IPR&D”) of $3.2 billion related to MK-3682 (in Phase 1 clinical development), deferred tax liabilities of $1.2 billion and other net assets and liabilities of approximately $350 million. MK-3682 is a nucleotide prodrug being evaluated for potential inclusion in the development of all oral, pan-genotypic fixed-dose combination regimens. The excess of the consideration transferred over the fair value of net assets acquired of $1.5 billion was recorded as goodwill that was allocated to the Pharmaceutical segment and is not deductible for tax purposes. The fair value of the identifiable intangible asset related to IPR&D was determined using an income approach, through which fair value is estimated based upon the asset’s probability adjusted future net cash flows, which reflects the stage of development of the project and the associated probability of successful completion. The net cash flows were then discounted to present value using a discount rate of 11.5%. This transaction closed on August 5, 2014, and accordingly, the results of operations of the acquired business have been included in the Company’s results of operations beginning after that date. Pro forma financial information has not been included because Idenix’s historical financial results are not significant when compared with the Company’s financial results.
	In May 2014, Merck entered into an agreement to sell certain ophthalmic products to Santen Pharmaceutical Co., Ltd. (“Santen”) in Japan and markets in Europe and Asia Pacific. The ophthalmic products included in the agreement are Cosopt (dorzolamide hydrochloride-timolol maleate ophthalmic solution), Cosopt PF (dorzolamide hydrochloride-timolol maleate ophthalmic solution) 2%/0.5%, Trusopt (dorzolamide hydrochloride ophthalmic solution) sterile ophthalmic solution 2%, Trusopt PF (dorzolamide hydrochloride ophthalmic solution) preservative-free, Timoptic (timolol maleate ophthalmic solution), Timoptic PF (timolol maleate preservative free ophthalmic solution in unit dose dispenser), Timoptic XE (timolol maleate ophthalmic gel forming solution), Saflutan (tafluprost) and Taptiqom (tafluprost-timolol maleate ophthalmic solution, in development). The agreement provides that Santen make upfront payments and additional payments based on defined sales milestones. Santen will also purchase supply of ophthalmology products covered by the agreement for a two- to five-year period. Upon closing of the transaction in most markets on July 1, 2014, the Company received $515 million of upfront payments from Santen, net of certain adjustments. Merck recognized a gain of $396 million on the transaction in the third quarter and first nine months of 2014 included in Other (income) expense, net. Upon closing of the remaining markets on October 1, 2014, the Company received an additional payment of approximately $50 million from Santen and will recognize an additional gain of approximately $100 million in the fourth quarter of 2014.
	In March 2014, Merck divested its Sirna Therapeutics, Inc. (“Sirna”) subsidiary to Alnylam Pharmaceuticals, Inc. (“Alnylam”) for consideration of $25 million and 2,520,044 shares of Alnylam common stock. Merck is eligible to receive future payments associated with the achievement of certain regulatory and commercial milestones, as well as royalties on future sales. Under the terms of the agreement, Merck received 85% of the Alnylam shares in the first quarter of 2014 (valued at $172 million at the time of closing) and the remaining 15% of the shares in the second quarter of 2014 (valued at $22 million at the time the shares were received). Merck recorded gains of $204 million in the first nine months of 2014 related to this transaction that are included in Other (income) expense, net. The excess of Merck’s tax basis in its investment in Sirna over the value received resulted in an approximate $300 million tax benefit recorded in the first nine months of 2014. In the second quarter of 2014, the Company recorded a $36 million impairment charge within Other (income) expense, net on the Alnylam shares received in the first quarter of 2014 as the Company determined these shares were other than temporarily impaired.
	In January 2014, Merck sold the U.S. marketing rights to Saphris (asenapine), an antipsychotic indicated for the treatment of schizophrenia and bipolar I disorder in adults to Forest Laboratories, Inc. (“Forest”). Under the terms of the agreement, Forest made upfront payments of $232 million, which were recorded in Sales in the first nine months of 2014, and will make additional payments to Merck based on defined sales milestones. In addition, as part of this transaction, Merck has agreed to supply product to Forest (subsequently acquired by Actavis plc) until patent expiry.
	In April 2013, Merck and Pfizer Inc. (“Pfizer”) announced that they had entered into a worldwide (except Japan) collaboration agreement for the development and commercialization of Pfizer’s ertugliflozin, an investigational oral sodium glucose cotransporter (“SGLT2”) inhibitor being evaluated for the treatment of type 2 diabetes. The Company has initiated Phase 3 clinical trials for ertugliflozin with Pfizer. Under the terms of the agreement, Merck and Pfizer will collaborate on the clinical development and commercialization of ertugliflozin and ertugliflozin-containing fixed-dose combinations with metformin and with Januvia (sitagliptin) tablets. Merck will continue to retain the rights to its existing portfolio of sitagliptin-containing products. Through the first nine months of 2013, Merck recorded research and development expenses of $60 million for upfront and milestone payments made to Pfizer. Pfizer will be eligible for additional payments associated with the achievement of pre-specified future clinical, regulatory and commercial milestones. The companies will share potential revenues and certain costs 60% to Merck and 40% to Pfizer. Each party will have certain manufacturing and supply obligations. The Company and Pfizer each have the right to terminate the agreement due to a material, uncured breach by, or insolvency of, the other party, or in the event of a safety issue. Pfizer has the right to terminate the agreement upon 12 months notice at any time following the first anniversary of the first commercial sale of a collaboration product, but must assign all rights to ertugliflozin to Merck. Upon termination of the agreement, depending upon the circumstances, the parties have varying rights and obligations with respect to the continued development and commercialization of ertugliflozin and certain payment obligations.
	In February 2013, Merck and Supera Farma Laboratorios S.A. (“Supera”), a Brazilian pharmaceutical company co-owned by Cristália and Eurofarma, established the previously announced joint venture that markets, distributes and sells a portfolio of pharmaceutical and branded generic products from Merck, Cristália and Eurofarma in Brazil. Merck owns 51% of the joint venture, and Cristália and Eurofarma collectively own 49%. The transaction was accounted for as an acquisition of a business; accordingly, the assets acquired and liabilities assumed were recorded at their respective fair values. This resulted in Merck recognizing intangible assets for currently marketed products of $89 million, IPR&D of $100 million, goodwill of $103 million, and deferred tax liabilities of $64 million. The Company also recorded increases to Noncontrolling interests and Other paid-in capital in the amounts of $112 million and $116 million, respectively. This transaction closed on February 1, 2013, and accordingly, the results of operations of the acquired business have been included in the Company’s results of operations beginning after that date. During the third quarter of 2014, as a result of changes in cash flow assumptions for certain compounds, the Company recorded $31 million of asset impairment charges related to IPR&D recorded in the Supera transaction. The changes in cash flow assumptions for these compounds, as well as for certain currently marketed products, also resulted in the write-off of the goodwill balance related to the joint venture with Supera, which was $93 million at current exchange rates. During the fourth quarter of 2013, as a result of changes in cash flow assumptions for certain compounds, the Company recorded $15 million of impairment charges related to the IPR&D recorded in the Supera transaction.
	Merck Consumer Care
	On October 1, 2014, the Company completed the previously announced sale of its Merck Consumer Care (“MCC”) business to Bayer AG (“Bayer”) for $14.2 billion, less customary closing adjustments as well as certain contingent amounts held back that will be payable upon the manufacturing site transfer in Canada and regulatory approval in Korea. Under the terms of the agreement, Bayer acquired Merck’s existing over-the-counter (“OTC”) business, including the global trademark and prescription rights for Claritin and Afrin. The Company expects the pretax gain from the sale of MCC to be approximately $11.0 billion.
	Information with respect to Consumer Care assets and liabilities held for sale at September 30 is as follows:
	($ millions)	30-Sep-14
	Assets
	Accounts receivable, net	$	79
	Inventories	278
	Deferred income taxes and other current assets	25
	Property, plant and equipment, net	212
	Goodwill	162
	Other intangibles, net	2,194
	Other assets	56
		$	3,006
	Liabilities
	Trade accounts payable	$	84
	Accrued and other current liabilities	114
	Deferred income taxes	561
	Other noncurrent liabilities	6
		$	765
	The Company also entered into the previously announced worldwide clinical development collaboration with Bayer to market and develop its portfolio of soluble guanylate cyclase (“sGC”) modulators. This includes Bayer’s Adempas (riociguat), the first member of this novel class of compounds. Adempas is approved to treat pulmonary arterial hypertension (“PAH”) and is the first and only drug treatment approved for patients with chronic thromboembolic pulmonary hypertension (“CTEPH”). Adempas is currently marketed in the United States and Europe for both PAH and CTEPH and in Japan for CTEPH. The two companies will equally share costs and profits from the collaboration and implement a joint development and commercialization strategy. The collaboration also includes clinical development of Bayer’s vericiguat, which is currently in Phase 2 trials for worsening heart failure, as well as opt-in rights for other early-stage sGC compounds in development at Bayer. Merck will in turn make available its early-stage sGC compounds under similar terms. In return for these broad collaboration rights, Merck made an upfront payment to Bayer of $1.0 billion with the potential for additional milestone payments upon the achievement of agreed-upon sales goals. For Adempas, Bayer will continue to lead commercialization in the Americas, while Merck will lead commercialization in the rest of the world. For vericiguat and other potential opt-in products, Bayer will lead in the rest of world and Merck will lead in the Americas. For all products and candidates included in the agreement, both companies will share in development costs and profits on sales and will have the right to co-promote in territories where they are not the lead. The Company and Bayer each have the right to terminate the agreement for cause on a product-by-product basis, for all products being developed and commercialized under the agreement (other than Adempas for which Bayer has no termination rights) in the event of the other party’s material, uncured breach related to any such product.
	Remicade/Simponi
	In 1998, a subsidiary of Schering-Plough entered into a licensing agreement with Centocor Ortho Biotech Inc. (“Centocor”), a Johnson & Johnson (“J&J”) company, to market Remicade, which is prescribed for the treatment of inflammatory diseases. In 2005, Schering-Plough’s subsidiary exercised an option under its contract with Centocor for license rights to develop and commercialize Simponi, a fully human monoclonal antibody. The Company has exclusive marketing rights to both products throughout Europe, Russia and Turkey. In December 2007, Schering-Plough and Centocor revised their distribution agreement regarding the development, commercialization and distribution of both Remicade and Simponi, extending the Company’s rights to exclusively market Remicade to match the duration of the Company’s exclusive marketing rights for Simponi. In addition, Schering-Plough and Centocor agreed to share certain development costs relating to Simponi’s auto-injector delivery system. On October 6, 2009, the European Commission approved Simponi as a treatment for rheumatoid arthritis and other immune system disorders in two presentations – a novel auto-injector and a prefilled syringe. As a result, the Company’s marketing rights for both products extend for 15 years from the first commercial sale of Simponi in the European Union (the “EU”) following the receipt of pricing and reimbursement approval within the EU. All profits derived from Merck’s exclusive distribution of the two products in these countries are equally divided between Merck and J&J.

Financial_Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Financial Instruments	'
	Financial Instruments
	Derivative Instruments and Hedging Activities
	The Company manages the impact of foreign exchange rate movements and interest rate movements on its earnings, cash flows and fair values of assets and liabilities through operational means and through the use of various financial instruments, including derivative instruments.
	A significant portion of the Company’s revenues and earnings in foreign affiliates is exposed to changes in foreign exchange rates. The objectives and accounting related to the Company’s foreign currency risk management program, as well as its interest rate risk management activities are discussed below.
	Foreign Currency Risk Management
	The Company has established revenue hedging, balance sheet risk management and net investment hedging programs to protect against volatility of future foreign currency cash flows and changes in fair value caused by volatility in foreign exchange rates.
	The objective of the revenue hedging program is to reduce the potential for longer-term unfavorable changes in foreign exchange rates to decrease the U.S. dollar value of future cash flows derived from foreign currency denominated sales, primarily the euro and Japanese yen. To achieve this objective, the Company will hedge a portion of its forecasted foreign currency denominated third-party and intercompany distributor entity sales that are expected to occur over its planning cycle, typically no more than three years into the future. The Company will layer in hedges over time, increasing the portion of third-party and intercompany distributor entity sales hedged as it gets closer to the expected date of the forecasted foreign currency denominated sales. The portion of sales hedged is based on assessments of cost-benefit profiles that consider natural offsetting exposures, revenue and exchange rate volatilities and correlations, and the cost of hedging instruments. The hedged anticipated sales are a specified component of a portfolio of similarly denominated foreign currency-based sales transactions, each of which responds to the hedged currency risk in the same manner. The Company manages its anticipated transaction exposure principally with purchased local currency put options, which provide the Company with a right, but not an obligation, to sell foreign currencies in the future at a predetermined price. If the U.S. dollar strengthens relative to the currency of the hedged anticipated sales, total changes in the options’ cash flows offset the decline in the expected future U.S. dollar equivalent cash flows of the hedged foreign currency sales. Conversely, if the U.S. dollar weakens, the options’ value reduces to zero, but the Company benefits from the increase in the U.S. dollar equivalent value of the anticipated foreign currency cash flows.
	In connection with the Company’s revenue hedging program, a purchased collar option strategy may be utilized. With a purchased collar option strategy, the Company writes a local currency call option and purchases a local currency put option. As compared to a purchased put option strategy alone, a purchased collar strategy reduces the upfront costs associated with purchasing puts through the collection of premium by writing call options. If the U.S. dollar weakens relative to the currency of the hedged anticipated sales, the purchased put option value of the collar strategy reduces to zero and the Company benefits from the increase in the U.S. dollar equivalent value of its anticipated foreign currency cash flows; however, this benefit would be capped at the strike level of the written call. If the U.S. dollar strengthens relative to the currency of the hedged anticipated sales, the written call option value of the collar strategy reduces to zero and the changes in the purchased put cash flows of the collar strategy would offset the decline in the expected future U.S. dollar equivalent cash flows of the hedged foreign currency sales.
	The Company may also utilize forward contracts in its revenue hedging program. If the U.S. dollar strengthens relative to the currency of the hedged anticipated sales, the increase in the fair value of the forward contracts offsets the decrease in the expected future U.S. dollar cash flows of the hedged foreign currency sales. Conversely, if the U.S. dollar weakens, the decrease in the fair value of the forward contracts offsets the increase in the value of the anticipated foreign currency cash flows.
	The fair values of these derivative contracts are recorded as either assets (gain positions) or liabilities (loss positions) in the Consolidated Balance Sheet. Changes in the fair value of derivative contracts are recorded each period in either current earnings or Other comprehensive income (“OCI”), depending on whether the derivative is designated as part of a hedge transaction and, if so, the type of hedge transaction. For derivatives that are designated as cash flow hedges, the effective portion of the unrealized gains or losses on these contracts is recorded in Accumulated other comprehensive income (“AOCI”) and reclassified into Sales when the hedged anticipated revenue is recognized. The hedge relationship is highly effective and hedge ineffectiveness has been de minimis. For those derivatives which are not designated as cash flow hedges, but serve as economic hedges of forecasted sales, unrealized gains or losses are recorded in Sales each period. The cash flows from both designated and non-designated contracts are reported as operating activities in the Consolidated Statement of Cash Flows. The Company does not enter into derivatives for trading or speculative purposes.
	The primary objective of the balance sheet risk management program is to mitigate the exposure of foreign currency denominated net monetary assets of foreign subsidiaries where the U.S. dollar is the functional currency from the effects of volatility in foreign exchange. In these instances, Merck principally utilizes forward exchange contracts, which enable the Company to buy and sell foreign currencies in the future at fixed exchange rates and economically offset the consequences of changes in foreign exchange from the monetary assets. Merck routinely enters into contracts to offset the effects of exchange on exposures denominated in developed country currencies, primarily the euro and Japanese yen. For exposures in developing country currencies, the Company will enter into forward contracts to partially offset the effects of exchange on exposures when it is deemed economical to do so based on a cost-benefit analysis that considers the magnitude of the exposure, the volatility of the exchange rate and the cost of the hedging instrument. The Company will also minimize the effect of exchange on monetary assets and liabilities by managing operating activities and net asset positions at the local level. The cash flows from these contracts are reported as operating activities in the Consolidated Statements of Cash Flows.
	Monetary assets and liabilities denominated in a currency other than the functional currency of a given subsidiary are remeasured at spot rates in effect on the balance sheet date with the effects of changes in spot rates reported in Other (income) expense, net. The forward contracts are not designated as hedges and are marked to market through Other (income) expense, net. Accordingly, fair value changes in the forward contracts help mitigate the changes in the value of the remeasured assets and liabilities attributable to changes in foreign currency exchange rates, except to the extent of the spot-forward differences. These differences are not significant due to the short-term nature of the contracts, which typically have average maturities at inception of less than one year.
	The Company also uses forward exchange contracts to hedge its net investment in foreign operations against movements in exchange rates. The forward contracts are designated as hedges of the net investment in a foreign operation. The Company hedges a portion of the net investment in certain of its foreign operations and measures ineffectiveness based upon changes in spot foreign exchange rates. The effective portion of the unrealized gains or losses on these contracts is recorded in foreign currency translation adjustment within OCI, and remains in AOCI until either the sale or complete or substantially complete liquidation of the subsidiary. The cash flows from these contracts are reported as investing activities in the Consolidated Statement of Cash Flows.
	Foreign exchange risk is also managed through the use of foreign currency debt. The Company’s senior unsecured euro-denominated notes have been designated as, and are effective as, economic hedges of the net investment in a foreign operation. Accordingly, foreign currency transaction gains or losses due to spot rate fluctuations on the euro-denominated debt instruments are included in foreign currency translation adjustment within OCI. Included in the cumulative translation adjustment are pretax gains (losses) of $166 million and $(33) million for the first nine months of 2014 and 2013, respectively, from the euro-denominated notes.
	Interest Rate Risk Management
	The Company may use interest rate swap contracts on certain investing and borrowing transactions to manage its net exposure to interest rate changes and to reduce its overall cost of borrowing. The Company does not use leveraged swaps and, in general, does not leverage any of its investment activities that would put principal capital at risk.
	At September 30, 2014, the Company was party to a total of 11 pay-floating, receive-fixed interest rate swap contracts designated as fair value hedges of fixed-rate notes in which the notional amounts match the amount of the hedged fixed-rate notes. There are four swaps maturing in 2016 with notional amounts of $250 million each that effectively convert the Company’s 0.70% fixed-rate notes due in 2016 to floating-rate instruments; four swaps maturing in 2018 with notional amounts of $250 million each that effectively convert the Company’s 1.30% fixed-rate notes due in 2018 to floating-rate instruments; and three swaps maturing in 2019, two with notional amounts of $200 million each, and one with a notional amount of $150 million, that effectively convert a portion of the Company’s 5.00% notes due in 2019 to floating rate instruments. The interest rate swap contracts are designated hedges of the fair value changes in the notes attributable to changes in the benchmark London Interbank Offered Rate (“LIBOR”) swap rate. The fair value changes in the notes attributable to changes in the LIBOR are recorded in interest expense and offset by the fair value changes in the swap contracts. In September 2014, the Company terminated four interest rate swap contracts that effectively converted the Company’s 6.00% fixed-rate notes due in 2017 to floating-rate instruments. As result of the swap terminations, the Company received $3 million in cash. The corresponding basis adjustment of the debt associated with the terminated interest rate swap contracts was deferred and is being amortized as a reduction of interest expense over the respective term of the notes. The cash flows from these contracts are reported as operating activities in the Consolidated Statement of Cash Flows.
	Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments:
			30-Sep-14									31-Dec-13
			Fair Value of Derivative						U.S. Dollar			Fair Value of Derivative						U.S. Dollar
	($ in millions)	Balance Sheet Caption	Asset			Liability			Notional			Asset			Liability			Notional
	Derivatives Designated as Hedging Instruments
	Interest rate swap contracts (non-current)	Other assets	$	8		$	—		$	550		$	13		$	—		$	1,550
	Interest rate swap contracts (non-current)	Other noncurrent liabilities	—			22			2,000			—			25			2,000
	Foreign exchange contracts (current)	Deferred income taxes and other current assets	627			—			7,157			493			—			4,427
	Foreign exchange contracts (non-current)	Other assets	491			—			6,238			515			—			6,676
	Foreign exchange contracts (current)	Accrued and other current liabilities	—			1			464			—			19			1,659
	Foreign exchange contracts (non-current)	Other noncurrent liabilities	—			1			120			—			—			—
			$	1,126		$	24		$	16,529		$	1,021		$	44		$	16,312
	Derivatives Not Designated as Hedging Instruments
	Foreign exchange contracts (current)	Deferred income taxes and other current assets	$	234		$	—		$	9,192		$	69		$	—		$	5,705
	Foreign exchange contracts (current)	Accrued and other current liabilities	—			70			4,687			—			140			7,892
			$	234		$	70		$	13,879		$	69		$	140		$	13,597
			$	1,360		$	94		$	30,408		$	1,090		$	184		$	29,909
	As noted above, the Company records its derivatives on a gross basis in the Consolidated Balance Sheet. The Company has master netting agreements with several of its financial institution counterparties (see Concentrations of Credit Risk below). The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes:
		30-Sep-14						31-Dec-13
	($ in millions)	Asset			Liability			Asset			Liability
	Gross amounts recognized in the consolidated balance sheet	$	1,360		$	94		$	1,090		$	184
	Gross amount subject to offset in master netting arrangements	(91		)	(91		)	(147		)	(147		)
	not offset in the consolidated balance sheet
	Cash collateral (received) posted	(942		)	—			(652		)	—
	Net amounts	$	327		$	3		$	291		$	37
	The table below provides information on the location and pretax gain or loss amounts for derivatives that are: (i) designated in a fair value hedging relationship, (ii) designated in a foreign currency cash flow hedging relationship, (iii) designated in a foreign currency net investment hedging relationship and (iv) not designated in a hedging relationship:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Derivatives designated in a fair value hedging relationship
	Interest rate swap contracts
	Amount of loss (gain) recognized in Other (income) expense, net on derivatives (1)	$	23		$	(33	)	$	2		$	1
	Amount of (gain) loss recognized in Other (income) expense, net on hedged item	(23		)	30			(3		)	(2		)
	Derivatives designated in foreign currency cash flow hedging relationships
	Foreign exchange contracts
	Amount of (gain) loss reclassified from AOCI to Sales	(42		)	1			(45		)	36
	Amount of (gain) loss recognized in OCI on derivatives	(433		)	165			(276		)	(219		)
	Derivatives designated in foreign currency net investment hedging relationships
	Foreign exchange contracts
	Amount of gain recognized in Other (income) expense, net on derivatives (2)	(1		)	(5		)	(3		)	(7		)
	Amount of gain recognized in OCI on derivatives	(116		)	(15		)	(67		)	(259		)
	Derivatives not designated in a hedging relationship
	Foreign exchange contracts
	Amount of (gain) loss recognized in Other (income) expense, net on derivatives (3)	(290		)	154			(314		)	146
	Amount of loss recognized in Sales	5			8			5			5
	(1) There was $3 million of ineffectiveness on the hedge during the third quarter and first nine months of 2013.
(2) There was no ineffectiveness on the hedge. Represents the amount excluded from hedge effectiveness testing.
(3) These derivative contracts mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.
At September 30, 2014, the Company estimates $256 million of pretax net unrealized gains on derivatives maturing within the next 12 months that hedge foreign currency denominated sales over that same period will be reclassified from AOCI to Sales. The amount ultimately reclassified to Sales may differ as foreign exchange rates change. Realized gains and losses are ultimately determined by actual exchange rates at maturity.
Investments in Debt and Equity Securities
Information on available-for-sale investments is as follows:
	30-Sep-14												31-Dec-13
	Fair			Amortized			Gross Unrealized						Fair			Amortized			Gross Unrealized
($ in millions)	Value			Cost			Gains			Losses			Value			Cost			Gains		Losses
Corporate notes and bonds	$	9,428		$	9,411		$	31		$	(14	)	$	7,054		$	7,037		$	32	$	(15	)
Commercial paper	2,121			2,121			—			—			1,206			1,206			—		—
U.S. government and agency securities	2,039			2,042			—			(3		)	1,236			1,239			1		(4		)
Asset-backed securities	1,440			1,441			1			(2		)	1,300			1,303			1		(4		)
Mortgage-backed securities	538			540			1			(3		)	476			479			2		(5		)
Foreign government bonds	456			456			—			—			125			126			—		(1		)
Equity securities	707			589			118			—			471			397			74		—
	$	16,729		$	16,600		$	151		$	(22	)	$	11,868		$	11,787		$	110	$	(29	)
Available-for-sale debt securities included in Short-term investments totaled $3.0 billion at September 30, 2014. Of the remaining debt securities, $12.1 billion mature within five years. At September 30, 2014 and December 31, 2013, there were no debt securities pledged as collateral.
Fair Value Measurements
Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company uses a fair value hierarchy which maximizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. There are three levels of inputs used to measure fair value with Level 1 having the highest priority and Level 3 having the lowest:
Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities.
Level 2 - Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3 - Unobservable inputs that are supported by little or no market activity. Level 3 assets are those whose values are determined using pricing models, discounted cash flow methodologies, or similar techniques with significant unobservable inputs, as well as instruments for which the determination of fair value requires significant judgment or estimation.
If the inputs used to measure the financial assets and liabilities fall within more than one level described above, the categorization is based on the lowest level input that is significant to the fair value measurement of the instrument.
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis
Financial assets and liabilities measured at fair value on a recurring basis are summarized below:
	Fair Value Measurements Using												Fair Value Measurements Using
	Quoted Prices			Significant			Significant			Total			Quoted Prices			Significant			Significant		Total
	In Active			Other			Unobservable						In Active			Other			Unobservable
	Markets for			Observable			Inputs						Markets for			Observable			Inputs
	Identical Assets			Inputs			(Level 3)						Identical Assets			Inputs			(Level 3)
	(Level 1)			(Level 2)									(Level 1)			(Level 2)
($ in millions)	30-Sep-14												31-Dec-13
Assets
Investments
Corporate notes and bonds	$	—		$	9,428		$	—		$	9,428		$	—		$	7,054		$	—	$	7,054
Commercial paper	—			2,121			—			2,121			—			1,206			—		1,206
U.S. government and agency securities	—			2,039			—			2,039			—			1,236			—		1,236
Asset-backed securities (1)	—			1,440			—			1,440			—			1,300			—		1,300
Mortgage-backed securities (1)	—			538			—			538			—			476			—		476
Foreign government bonds	—			456			—			456			—			125			—		125
Equity securities	447			—			—			447			238			—			—		238
	447			16,022			—			16,469			238			11,397			—		11,635
Other assets
Securities held for employee compensation	198			62			—			260			186			47			—		233
Derivative assets (2)
Purchased currency options	—			918			—			918			—			868			—		868
Forward exchange contracts	—			434			—			434			—			209			—		209
Interest rate swaps	—			8			—			8			—			13			—		13
	—			1,360			—			1,360			—			1,090			—		1,090
Total assets	$	645		$	17,444		$	—		$	18,089		$	424		$	12,534		$	—	$	12,958
Liabilities
Derivative liabilities (2)
Forward exchange contracts	$	—		$	29		$	—		$	29		$	—		$	134		$	—	$	134
Written currency options	—			43			—			43			—			25			—		25
Interest rate swaps	—			22			—			22			—			25			—		25
Total liabilities	$	—		$	94		$	—		$	94		$	—		$	184		$	—	$	184
(1)	Primarily all of the asset-backed securities are highly-rated (Standard & Poor’s rating of AAA and Moody’s Investors Service rating of Aaa), secured primarily by credit card, auto loan, and home equity receivables, with weighted-average lives of primarily 5 years or less. Mortgage-backed securities represent AAA-rated securities issued or unconditionally guaranteed as to payment of principal and interest by U.S. government agencies.
(2)	The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.
There were no transfers between Level 1 and Level 2 during the first nine months of 2014. As of September 30, 2014, Cash and cash equivalents of $11.4 billion included $10.4 billion of cash equivalents (considered Level 2 in the fair value hierarchy). The Company has liabilities related to contingent consideration (considered Level 3 in the fair value hierarchy) associated with business combinations, the fair values of which were $75 million and $69 million at September 30, 2014 and December 31, 2013, respectively.
Other Fair Value Measurements
Some of the Company’s financial instruments, such as cash and cash equivalents, receivables and payables, are reflected in the balance sheet at carrying value, which approximates fair value due to their short-term nature.
The estimated fair value of loans payable and long-term debt (including current portion) at September 30, 2014, was $29.0 billion compared with a carrying value of $27.8 billion and at December 31, 2013, was $25.5 billion compared with a carrying value of $25.1 billion. Fair value was estimated using recent observable market prices and would be considered Level 2 in the fair value hierarchy.
Concentrations of Credit Risk
On an ongoing basis, the Company monitors concentrations of credit risk associated with corporate and government issuers of securities and financial institutions with which it conducts business. Credit exposure limits are established to limit a concentration with any single issuer or institution. Cash and investments are placed in instruments that meet high credit quality standards as specified in the Company’s investment policy guidelines.
The majority of the Company’s accounts receivable arise from product sales in the United States and Europe and are primarily due from drug wholesalers and retailers, hospitals, government agencies, managed health care providers and pharmacy benefit managers. The Company monitors the financial performance and creditworthiness of its customers so that it can properly assess and respond to changes in their credit profile. The Company also continues to monitor economic conditions, including the volatility associated with international sovereign economies, and associated impacts on the financial markets and its business, taking into consideration global economic conditions and the ongoing sovereign debt issues in certain European countries. The Company continues to monitor the credit and economic conditions within Greece, Italy, Spain and Portugal, among other members of the EU. These economic conditions, as well as inherent variability of timing of cash receipts, have resulted in, and may continue to result in, an increase in the average length of time that it takes to collect accounts receivable outstanding. As such, time value of money discounts have been recorded for those customers for which collection of accounts receivable is expected to be in excess of one year. At September 30, 2014 and December 31, 2013, Other assets included $275 million of accounts receivable not expected to be collected within one year. The Company does not expect to have write-offs or adjustments to accounts receivable which would have a material adverse effect on its financial position, liquidity or results of operations.
At September 30, 2014, the Company’s accounts receivable in Greece, Italy, Spain and Portugal totaled approximately $900 million. Of this amount, hospital and public sector receivables were approximately $590 million in the aggregate, of which approximately 12%, 37%, 41% and 13% related to Greece, Italy, Spain and Portugal, respectively. At September 30, 2014, the Company’s total net accounts receivable outstanding for more than one year were approximately $165 million, of which approximately 45% related to accounts receivable in Greece, Italy, Spain and Portugal, mostly comprised of hospital and public sector receivables.
Additionally, the Company continues to expand in the emerging markets. Payment terms in these markets tend to be longer, resulting in an increase in accounts receivable balances in certain of these markets.
Derivative financial instruments are executed under International Swaps and Derivatives Association master agreements. The master agreements with several of the Company’s financial institution counterparties also include credit support annexes. These annexes contain provisions that require collateral to be exchanged depending on the value of the derivative assets and liabilities, the Company’s credit rating, and the credit rating of the counterparty. As of September 30, 2014 and December 31, 2013, the Company had received cash collateral of $942 million and $652 million, respectively, from various counterparties and the obligation to return such collateral is recorded in Accrued and other current liabilities. The Company had not advanced any cash collateral to counterparties as of September 30, 2014 or December 31, 2013.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	Inventories
	Inventories consisted of:
	($ in millions)	30-Sep-14		31-Dec-13
	Finished goods	$	1,811	$	1,738
	Raw materials and work in process	5,350		5,894
	Supplies	212		225
	Total (approximates current cost)	7,373		7,857
	Increase to LIFO costs	220		73
		$	7,593	$	7,930
	Recognized as:
	Inventories	$	5,819	$	6,226
	Other assets	1,774		1,704
	Amounts recognized as Other assets are comprised almost entirely of raw materials and work in process inventories. At September 30, 2014 and December 31, 2013, these amounts included $1.7 billion and $1.5 billion, respectively, of inventories not expected to be sold within one year. In addition, these amounts included $113 million and $177 million at September 30, 2014 and December 31, 2013, respectively, of inventories produced in preparation for product launches.

Other_Intangibles

Other Intangibles	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Other Intangibles	'
	Other Intangibles
	In connection with mergers and acquisitions, the Company measures the fair value of marketed products and research and development pipeline programs and capitalizes these amounts. During the third quarter and first nine months of 2014, the Company recorded intangible asset impairment charges of $412 million and $1.1 billion, respectively, within Materials and production costs related to certain products marketed by the Company for the treatment of chronic HCV. Sales of PegIntron, Victrelis and Rebetol are being adversely affected by loss of market share or patient treatment delays in markets anticipating the availability of new therapeutic options. During the second quarter, these trends accelerated more rapidly than previously anticipated by the Company, which led to changes in the cash flow assumptions for both PegIntron and Victrelis. These revisions to cash flows indicated that the PegIntron and Victrelis intangible asset values were not recoverable on an undiscounted cash flows basis. The Company utilized market participant assumptions to determine its best estimate of the fair values of the intangible assets related to PegIntron and Victrelis that, when compared with their related carrying values, resulted in impairment charges of $523 million for PegIntron and $137 million for Victrelis. During the third quarter of 2014, rapid developments in the competitive HCV treatment market led to market share losses that were greater than the Company had predicted, causing incremental deterioration of future cash flow projections that resulted in additional impairment charges of $270 million for PegIntron and $107 million for Victrelis, as well as an impairment charge of $35 million for Rebetol.
	During the first nine months of 2013, the Company recorded an intangible asset impairment charge of $330 million within Materials and production costs resulting from lower cash flow projections for Saphris/Sycrest due to reduced expectations in international markets and in the United States. These revisions to cash flows indicated that the Saphris/Sycrest intangible asset value was not recoverable on an undiscounted cash flows basis. The Company utilized market participant assumptions and considered several different scenarios to determine its best estimate of the fair value of the intangible asset related to Saphris/Sycrest that, when compared with its related carrying values, resulted in the impairment charge noted above.
	In addition, in the third quarter and first nine months of 2014, the Company recorded $36 million of IPR&D impairment charges within Research and development expenses primarily as a result of changes in cash flow assumptions for certain compounds obtained in connection with the Supera joint venture (see Note 3). During the first nine months of 2013, the Company recorded $264 million of IPR&D impairment charges within Research and development expenses. Of this amount, $181 million related to the write-off of the intangible asset associated with preladenant as a result of the discontinuation of the clinical development program for this compound. The remaining impairment charges for the first nine months of 2013 related to changes in cash flow assumptions for certain compounds, as well as for pipeline programs that had previously been deprioritized and were subsequently deemed to have no alternative use in the period.
	The Company may recognize additional non-cash impairment charges in the future related to other marked products or pipeline programs and such charges could be material.

Joint_Ventures_and_Other_Equit

Joint Ventures and Other Equity Method Affiliates	9 Months Ended
	Sep. 30, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
Joint Ventures and Other Equity Method Affiliates	'
	Joint Ventures and Other Equity Method Affiliates
	Equity income from affiliates reflects the performance of the Company’s joint ventures and other equity method affiliates and was comprised of the following:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
	($ in millions)	2014		2013		2014		2013
	AstraZeneca LP (1)	$	—	$	72	$	192	$	302
	Other (2)	24		30		49		49
		$	24	$	102	$	241	$	351
	(1)	As noted below, as of July 1, 2014, the Company no longer records equity income from AZLP.
	(2) Includes results from Sanofi Pasteur MSD.
	AstraZeneca LP
	In 1998, Merck and Astra completed the restructuring of the ownership and operations of their existing joint venture whereby Merck acquired Astra’s interest in KBI Inc. (“KBI”) and contributed KBI’s operating assets to a new U.S. limited partnership, Astra Pharmaceuticals L.P. (the “Partnership”), in exchange for a 1% limited partner interest. Astra contributed the net assets of its wholly owned subsidiary, Astra USA, Inc., to the Partnership in exchange for a 99% general partner interest. The Partnership, renamed AstraZeneca LP (“AZLP”) upon Astra’s 1999 merger with Zeneca Group Plc, became the exclusive distributor of the products for which KBI retained rights.
	On June 30, 2014, AstraZeneca exercised its option to purchase Merck’s interest in KBI for $419 million in cash. Of this amount, $327 million reflects an estimate of the fair value of Merck’s interest in Nexium and Prilosec. This portion of the exercise price, which is subject to a true-up in 2018 based on actual sales from closing in 2014 to June 2018, was deferred and is being recognized over time in Other (income) expense, net as the contingency is eliminated as sales occur. The remaining exercise price of $91 million primarily represents a multiple of ten times Merck’s average 1% annual profit allocation in the partnership for the three years prior to exercise. Merck recognized the $91 million as a gain in the first nine months of 2014 within Other (income) expense, net. As a result of AstraZeneca’s option exercise, the Company’s remaining interest in AZLP was redeemed. Accordingly, the Company also recognized a non-cash gain of approximately $650 million in the first nine months of 2014 within Other (income) expense, net resulting from the retirement of $2.4 billion of KBI preferred stock (see Note 10), the elimination of the Company’s $1.4 billion investment in AZLP and a $340 million reduction of goodwill. This transaction resulted in a net tax benefit of $517 million in the first nine months of 2014 primarily reflecting the reversal of deferred taxes on the AZLP investment balance.
	As a result of AstraZeneca exercising its option, as of July 1, 2014, the Company no longer records equity income from AZLP and supply sales to AZLP have terminated.
	Summarized financial information for AZLP is as follows:
		Six Months Ended		Three Months Ended September 30,		Nine Months Ended
		June 30,				September 30,
	($ in millions)	2014		2013		2013
	Sales	$	2,205	$	1,083	$	3,383
	Materials and production costs	1,044		554		1,681
	Other expense, net	604		398		1,198
	Income before taxes (1)	$	557	$	131	$	504
	(1)	Merck’s partnership returns from AZLP were generally contractually determined as noted above and were not based on a percentage of income from AZLP, other than with respect to Merck’s 1% limited partnership interest.

LongTerm_Debt_Notes

Long-Term Debt (Notes)	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Debt Disclosure [Text Block]	'
	8	Long-Term Debt
	In October 2014, the Company issued euro-denominated senior unsecured notes consisting of €1.0 billion principal amount of 1.125% notes due 2021, €1.0 billion principal amount of 1.875% notes due 2026 and €500 million principal amount of 2.5% notes due 2034. Interest on the notes is payable annually. The notes of each series are redeemable in whole or in part at any time at the Company’s option at varying redemption prices. The net proceeds of the offering of $3.1 billion were used in part to repay debt that was validly tendered in connection with tender offers launched by the Company for certain outstanding notes and debentures. The Company paid $2.5 billion in aggregate consideration (applicable purchase price together with accrued interest) to redeem $1.8 billion principal amount of debt. In addition, Merck announced its intention to redeem its $1.0 billion 4.00% Notes due 2015 and its $1.0 billion 6.00% Senior Notes due 2017. The Company anticipates it will record a pretax loss of approximately $650 million in the fourth quarter of 2014 in connection with these transactions.
	Also, in October 2014, $1.9 billion of 5.375% Euro denominated notes matured in accordance with their terms.
	In August 2014, the Company terminated its existing credit facility and entered into a new $6.0 billion, five-year credit facility that matures in August 2019. The facility provides backup liquidity for the Company’s commercial paper borrowing facility and is to be used for general corporate purposes. The Company has not drawn funding from this facility.

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Contingencies	'
	Contingencies
	The Company is involved in various claims and legal proceedings of a nature considered normal to its business, including product liability, intellectual property, and commercial litigation, as well as additional matters such as antitrust actions and environmental matters. Except for the Vioxx Litigation (as defined below) for which a separate assessment is provided in this Note, in the opinion of the Company, it is unlikely that the resolution of these matters will be material to the Company’s financial position, results of operations or cash flows.
	Given the nature of the litigation discussed below, including the Vioxx Litigation, and the complexities involved in these matters, the Company is unable to reasonably estimate a possible loss or range of possible loss for such matters until the Company knows, among other factors, (i) what claims, if any, will survive dispositive motion practice, (ii) the extent of the claims, including the size of any potential class, particularly when damages are not specified or are indeterminate, (iii) how the discovery process will affect the litigation, (iv) the settlement posture of the other parties to the litigation and (v) any other factors that may have a material effect on the litigation.
	The Company records accruals for contingencies when it is probable that a liability has been incurred and the amount can be reasonably estimated. These accruals are adjusted periodically as assessments change or additional information becomes available. For product liability claims, a portion of the overall accrual is actuarially determined and considers such factors as past experience, number of claims reported and estimates of claims incurred but not yet reported. Individually significant contingent losses are accrued when probable and reasonably estimable. Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable.
	The Company’s decision to obtain insurance coverage is dependent on market conditions, including cost and availability, existing at the time such decisions are made. The Company has evaluated its risks and has determined that the cost of obtaining product liability insurance outweighs the likely benefits of the coverage that is available and, as such, has no insurance for certain product liabilities effective August 1, 2004.
	Vioxx Litigation
	Product Liability Lawsuits
	As previously disclosed, Merck is a defendant in approximately 50 federal and state lawsuits (the “Vioxx Product Liability Lawsuits”) alleging personal injury as a result of the use of Vioxx. Most of these cases are coordinated in a multidistrict litigation in the U.S. District Court for the Eastern District of Louisiana (the “Vioxx MDL”) before Judge Eldon E. Fallon.
	As previously disclosed, Merck is also a defendant in approximately 30 putative class action lawsuits alleging economic injury as a result of the purchase of Vioxx. All but two of those cases are in the Vioxx MDL. Merck has reached a resolution, approved by Judge Fallon, of these class actions in the Vioxx MDL. Under the settlement, Merck will pay up to $23 million to pay all properly documented claims submitted by class members, approved attorneys’ fees and expenses, and approved settlement notice costs and certain other administrative expenses. The court entered an order approving the settlement in January 2014. One objector to the settlement has filed an appeal from the approval order, which is fully briefed and pending before the U.S. Court of Appeals for the Fifth Circuit.
	Merck is also a defendant in lawsuits brought by state Attorneys General of three states — Alaska, Montana and Utah. A fourth action, brought by the Attorney General of Mississippi, was settled and dismissed earlier this year. The remaining three actions were pending in the Vioxx MDL proceeding, although Judge Fallon asked that the Judicial Panel on Multidistrict Litigation (“JPML”) remand the cases to their original federal courts. The JPML issued conditional remand orders in all three cases, and Merck’s motions to vacate the conditional remand orders in all three cases were heard without oral argument at the JPML’s October 2, 2014 hearing in Louisville, Kentucky. On October 10, 2014, the JPML issued an order remanding the three actions back to their original federal courts. These three actions allege that Merck misrepresented the safety of Vioxx and seek recovery for expenditures on Vioxx by government-funded health care programs, such as Medicaid, and/or penalties for alleged Consumer Fraud Act violations.
	Shareholder Lawsuits
	As previously disclosed, in addition to the Vioxx Product Liability Lawsuits, various putative class actions and individual lawsuits under federal securities laws and state laws have been filed against Merck and various current and former officers and directors (the “Vioxx Securities Lawsuits”). The Vioxx Securities Lawsuits are coordinated in a multidistrict litigation in the U.S. District Court for the District of New Jersey before Judge Stanley R. Chesler, and have been consolidated for all purposes. In August 2011, Judge Chesler granted in part and denied in part Merck’s motion to dismiss the Fifth Amended Class Action Complaint in the consolidated securities action. Among other things, the claims based on statements made on or after the voluntary withdrawal of Vioxx on September 30, 2004, have been dismissed. In October 2011, defendants answered the Fifth Amended Class Action Complaint. In April 2012, plaintiffs filed a motion for class certification and, in January 2013, Judge Chesler granted that motion. In March 2013, plaintiffs filed a motion for leave to amend their complaint to add certain allegations to expand the class period. In May 2013, the court denied plaintiffs’ motion for leave to amend their complaint to expand the class period, but granted plaintiffs’ leave to amend their complaint to add certain allegations within the existing class period. In June 2013, plaintiffs filed their Sixth Amended Class Action Complaint. In July 2013, defendants answered the Sixth Amended Class Action Complaint. Discovery has been completed and is now closed. Under the court’s scheduling order, dispositive motions have been fully briefed.
	As previously disclosed, several individual securities lawsuits filed by foreign institutional investors also are consolidated with the Vioxx Securities Lawsuits. In October 2011, plaintiffs filed amended complaints in each of the pending individual securities lawsuits. Also in October 2011, an individual securities lawsuit (the “KBC Lawsuit”) was filed in the District of New Jersey by several foreign institutional investors; that case is also consolidated with the Vioxx Securities Lawsuits. In January 2012, defendants filed motions to dismiss in one of the individual lawsuits (the “ABP Lawsuit”). Briefing on the motions to dismiss was completed in March 2012. In August 2012, Judge Chesler granted in part and denied in part the motions to dismiss the ABP Lawsuit. Among other things, certain alleged misstatements and omissions were dismissed as inactionable and all state law claims were dismissed in full. In September 2012, defendants answered the complaints in all individual actions other than the KBC Lawsuit; on the same day, defendants moved to dismiss the complaint in the KBC Lawsuit on statute of limitations grounds. In December 2012, Judge Chesler denied the motion to dismiss the KBC Lawsuit and, in January 2013, defendants answered the complaint in the KBC Lawsuit. Discovery has been completed and is now closed. Under the court’s scheduling order, dispositive motions have been fully briefed. In March and April 2014, four additional individual securities complaints were filed by institutional investors that opted out of the class action referred to above. The new complaints are substantially similar to the complaints in the other individual securities lawsuits.
	Insurance
	The Company has Directors and Officers insurance coverage applicable to the Vioxx Securities Lawsuits with remaining stated upper limits of approximately $145 million, which is currently being used to partially fund the Company’s legal fees. As a result of the previously disclosed insurance arbitration, additional insurance coverage for these claims should also be available, if needed, under upper-level excess policies that provide coverage for a variety of risks. There are disputes with the insurers about the availability of some or all of the Company’s insurance coverage for these claims and there are likely to be additional disputes. The amounts actually recovered under the policies discussed in this paragraph may be less than the stated upper limits.
	International Lawsuits
	As previously disclosed, in addition to the lawsuits discussed above, Merck has been named as a defendant in litigation relating to Vioxx in Brazil, Canada, Europe and Israel (collectively, the “Vioxx International Lawsuits”). As previously disclosed, the Company has entered into an agreement to resolve all claims related to Vioxx in Canada pursuant to which the Company will pay a minimum of approximately $21 million but not more than an aggregate maximum of approximately $36 million. The agreement has been approved by courts in Canada’s provinces.
	Reserves
	The Company believes that it has meritorious defenses to the remaining Vioxx Product Liability Lawsuits, Vioxx Securities Lawsuits and Vioxx International Lawsuits (collectively, the “Vioxx Litigation”) and will vigorously defend against them. In view of the inherent difficulty of predicting the outcome of litigation, particularly where there are many claimants and the claimants seek indeterminate damages, the Company is unable to predict the outcome of these matters and, at this time, cannot reasonably estimate the possible loss or range of loss with respect to the remaining Vioxx Litigation. The Company has established a reserve with respect to the Canadian settlement, certain other Vioxx Product Liability Lawsuits and other immaterial settlements related to certain Vioxx International Lawsuits. The Company also has an immaterial remaining reserve relating to the previously disclosed Vioxx investigation for the non-participating states with which litigation is continuing. The Company has established no other liability reserves with respect to the Vioxx Litigation. Unfavorable outcomes in the Vioxx Litigation could have a material adverse effect on the Company’s financial position, liquidity and results of operations.
	Other Product Liability Litigation
	Fosamax
	As previously disclosed, Merck is a defendant in product liability lawsuits in the United States involving Fosamax (the “Fosamax Litigation”). As of September 30, 2014, approximately 5,555 cases, which include approximately 5,760 plaintiff groups, had been filed and were pending against Merck in either federal or state court, including one case which seeks class action certification, as well as damages and/or medical monitoring. In approximately 1,070 of these actions, plaintiffs allege, among other things, that they have suffered osteonecrosis of the jaw (“ONJ”), generally subsequent to invasive dental procedures, such as tooth extraction or dental implants and/or delayed healing, in association with the use of Fosamax. In addition, plaintiffs in approximately 4,485 of these actions generally allege that they sustained femur fractures and/or other bone injuries (“Femur Fractures”) in association with the use of Fosamax.
	In December 2013, Merck reached an agreement in principle with the Plaintiffs’ Steering Committee (“PSC”) in the Fosamax ONJ MDL (as defined below) to resolve pending ONJ cases not on appeal in the Fosamax ONJ MDL and in the state courts for an aggregate amount of $27.7 million, which the Company recorded as a liability in the fourth quarter of 2013. Merck and the PSC subsequently formalized the terms of this agreement in a Master Settlement Agreement (“ONJ Master Settlement Agreement”) that was executed in April 2014. All of plaintiffs’ counsel have advised the Company that they intend to participate in the settlement plan. As a condition to the settlement, 100% of the state and federal ONJ plaintiffs must also agree to participate in the settlement plan or Merck can either terminate the ONJ Master Settlement Agreement, or waive the 100% participation requirement and agree to a lesser funding amount for the settlement fund. On July 14, 2014, Merck elected to proceed with the ONJ Master Settlement Agreement at a reduced funding level since the current participation level is approximately 95%. In addition, the judge overseeing the Fosamax ONJ MDL granted a motion filed by Merck and has entered an order that requires approximately 40 non-participants whose cases are filed in the Fosamax ONJ MDL to submit expert reports in order for their cases to proceed any further. The ONJ Master Settlement Agreement has no effect on the cases alleging Femur Fractures discussed below.
	Cases Alleging ONJ and/or Other Jaw Related Injuries
	In August 2006, the JPML ordered that certain Fosamax product liability cases pending in federal courts nationwide should be transferred and consolidated into one multidistrict litigation (the “Fosamax ONJ MDL”) for coordinated pre-trial proceedings. The Fosamax ONJ MDL has been transferred to Judge John Keenan in the U.S. District Court for the Southern District of New York. As a result of the JPML order, approximately 785 of the cases are before Judge Keenan, although, as noted above, these cases are subject to the pending settlement.
	In addition, in July 2008, an application was made by the Atlantic County Superior Court of New Jersey requesting that all of the Fosamax cases pending in New Jersey be considered for mass tort designation and centralized management before one judge in New Jersey. In October 2008, the New Jersey Supreme Court ordered that all pending and future actions filed in New Jersey arising out of the use of Fosamax and seeking damages for existing dental and jaw-related injuries, including ONJ, but not solely seeking medical monitoring, be designated as a mass tort for centralized management purposes. As of September 30, 2014, approximately 275 ONJ cases were pending against Merck in Atlantic County, New Jersey, although these cases are also subject to the pending settlement described above.
	Cases Alleging Femur Fractures
	In March 2011, Merck submitted a Motion to Transfer to the JPML seeking to have all federal cases alleging Femur Fractures consolidated into one multidistrict litigation for coordinated pre-trial proceedings. The Motion to Transfer was granted in May 2011, and all federal cases involving allegations of Femur Fracture have been or will be transferred to a multidistrict litigation in the District of New Jersey (the “Fosamax Femur Fracture MDL”). As a result of the JPML order, approximately 1,035 cases were pending in the Fosamax Femur Fracture MDL as of September 30, 2014. A Case Management Order was entered requiring the parties to review 33 cases. Judge Joel Pisano selected four cases from that group to be tried as the initial bellwether cases in the Fosamax Femur Fracture MDL. The first bellwether case, Glynn v. Merck, began on April 8, 2013, and the jury returned a verdict in Merck’s favor on April 29, 2013; in addition, on June 27, 2013, Judge Pisano granted Merck’s motion for judgment as a matter of law in the Glynn case and held that the plaintiff’s failure to warn claim was preempted by federal law. Judge Pisano set a May 5, 2014, trial date for the bellwether trial of a case in which the alleged injury took place after January 31, 2011. Following the completion of fact discovery, the court selected Sweet v. Merck as the next Fosamax Femur Fracture MDL case to be tried on May 5, 2014, but plaintiffs subsequently dismissed that case. As a result, the May 2014 trial date was withdrawn.
	In addition, Judge Pisano entered an order in August 2013 requiring plaintiffs in the Fosamax Femur Fracture MDL to show cause why those cases asserting claims for a femur fracture injury that took place prior to September 14, 2010, should not be dismissed based on the court’s preemption decision in the Glynn case. Plaintiffs filed their responses to the show cause order at the end of September 2013 and Merck filed its reply to those responses at the end of October 2013. A hearing on the show cause order was held in January 2014 and, on March 26, 2014, Judge Pisano issued an opinion finding that all claims of the approximately 650 plaintiffs who allegedly suffered injuries prior to September 14, 2010 were preempted and ordered that those cases be dismissed. The majority of those plaintiffs are appealing that ruling to the U.S. Court of Appeals for the Third Circuit. Furthermore, on June 17, 2014, Judge Pisano granted Merck summary judgment in the Gaynor v. Merck case and found that Merck’s updates in January 2011 to the Fosamax label regarding atypical femur fractures were adequate as a matter of law and that Merck adequately communicated those changes. The plaintiffs in Gaynor have appealed Judge Pisano’s decision to the Third Circuit. In August 2014, Merck filed a motion requesting that Judge Pisano enter a further order requiring all remaining plaintiffs in the Fosamax Femur Fracture MDL to show cause why their cases should not be dismissed based on the court’s preemption decision and its ruling in the Gaynor case that the 2011 Merck label is adequate as a matter of law. Plaintiffs have opposed that motion and asked the court to stay the remaining cases in the Fosamax Femur Fracture MDL until the Third Circuit rules on their appeal of Judge Pisano’s preemption decision. In September 2014, Judge Pisano also ordered the parties to participate in a mediation process.
	As of September 30, 2014, approximately 2,920 cases alleging Femur Fractures have been filed in New Jersey state court and were pending before Judge Carol E. Higbee in Atlantic County Superior Court until she was reassigned to the New Jersey Appellate Division in August 2014. The parties selected an initial group of 30 cases to be reviewed through fact discovery. Two additional groups of 50 cases each to be reviewed through fact discovery were selected in November 2013 and March 2014, respectively. In September 2014, Judge Julio Mendez, the Assignment Judge for Atlantic County, advised that the Fosamax Femur Fracture cases will be transferred to the Multi-County Litigation Vicinage in Middlesex County.
	As of September 30, 2014, approximately 520 cases alleging Femur Fractures have been filed in California state court. A petition was filed seeking to coordinate all Femur Fracture cases filed in California state court before a single judge in Orange County, California. The petition was granted and Judge Thierry Colaw is currently presiding over the coordinated proceedings. In March 2014, the court directed that a group of 10 discovery pool cases be reviewed through fact discovery and subsequently scheduled the Galper v. Merck case as the first trial for February 2015. Two additional trials are scheduled for May and July 2015.
	Additionally, there are five Femur Fracture cases pending in other state courts.
	Discovery is ongoing in the Fosamax Femur Fracture MDL and in state courts where Femur Fracture cases are pending and the Company intends to defend against these lawsuits.
	Januvia/Janumet
	As previously disclosed, Merck is a defendant in product liability lawsuits in the United States involving Januvia and/or Janumet. As of September 30, 2014, approximately 700 product user claims were served on, and are pending against, Merck alleging generally that use of Januvia and/or Janumet caused the development of pancreatic cancer. These complaints were filed in several different state and federal courts. Most of the claims are pending in a consolidated multidistrict litigation proceeding in the U.S. District Court for the Southern District of California called “In re Incretin-Based Therapies Products Liability Litigation.” That proceeding includes federal lawsuits alleging pancreatic cancer due to use of the following medicines: Januvia, Janumet, Byetta and Victoza, the latter two of which are products manufactured by other pharmaceutical companies. In addition to the cases noted above, the Company has agreed, as of September 30, 2014, to toll the statute of limitations for 19 additional claims. The Company intends to defend against these lawsuits.
	NuvaRing
	As previously disclosed, beginning in May 2007, a number of complaints were filed in various jurisdictions asserting claims against the Company’s subsidiaries Organon USA, Inc., Organon Pharmaceuticals USA, Inc., Organon International (collectively, “Organon”), and the Company arising from Organon’s marketing and sale of NuvaRing (the “NuvaRing Litigation”), a combined hormonal contraceptive vaginal ring. The plaintiffs contend that Organon and Schering-Plough, among other things, failed to adequately design and manufacture NuvaRing and failed to adequately warn of the alleged increased risk of venous thromboembolism (“VTE”) posed by NuvaRing, and/or downplayed the risk of VTE. The plaintiffs seek damages for injuries allegedly sustained from their product use, including some alleged deaths, heart attacks and strokes. The majority of the cases are currently pending in a federal multidistrict litigation (the “NuvaRing MDL”) venued in Missouri and in a coordinated proceeding in New Jersey state court.
	As of September 30, 2014, there were approximately 1,945 NuvaRing cases, the vast majority of which are subject to the settlement agreement discussed below. Of these cases, approximately 1,720 are or will be pending in the NuvaRing MDL in the U.S. District Court for the Eastern District of Missouri before Judge Rodney Sippel, and approximately 215 are pending in coordinated proceedings in the Bergen County Superior Court of New Jersey before Judge Brian R. Martinotti. Seven additional cases are pending in various other state courts, including cases in a coordinated state proceeding in the San Francisco Superior Court in California before Judge John E. Munter.
	Merck and negotiating plaintiffs’ counsel agreed to a settlement of the NuvaRing Litigation to resolve all filed cases as of February 7, 2014, and all unfiled claims under retainer by counsel prior to that date. Pursuant to this settlement agreement, which became effective as of June 4, 2014, Merck paid a lump total settlement of $100 million to resolve more than 95% of the cases filed and under retainer by counsel as of February 7, 2014. The vast majority of the plaintiffs with pending lawsuits have opted into the settlement and all participants in the settlement have tendered dismissals of their cases to the settlement administrator. The dismissals will be filed with the courts upon completion of the settlement administration process. The Company has certain insurance coverage available to it, which is currently being used to partially fund the Company’s legal fees. This insurance coverage has also been used to fund the settlement. Any plaintiff not participating in the settlement who chooses to proceed with their case, as well as any future plaintiffs, in the NuvaRing MDL or New Jersey state court are and will be obligated to meet various discovery and evidentiary requirements under the case management orders of the NuvaRing MDL and New Jersey state court. Plaintiffs who fail to fully and timely satisfy these requirements under set deadlines will be subject to an Order to Show Cause why their case should not be dismissed with prejudice.
	Propecia/Proscar
	As previously disclosed, Merck is a defendant in product liability lawsuits in the United States involving Propecia and/or Proscar. As of September 30, 2014, approximately 1,245 lawsuits involving a total of approximately 1,515 plaintiffs (in a few instances spouses are joined as plaintiffs in the suits) who allege that they have experienced persistent sexual side effects following cessation of treatment with Propecia and/or Proscar have been filed against Merck. Approximately 45 of the plaintiffs also allege that Propecia or Proscar has caused or can cause prostate cancer or male breast cancer. The lawsuits have been filed in various federal courts and in state court in New Jersey. The federal lawsuits have been consolidated for pretrial purposes in a federal multidistrict litigation before Judge John Gleeson of the Eastern District of New York. The matters pending in state court in New Jersey have been consolidated before Judge Jessica Mayer in Middlesex County. In addition, there is one matter pending in federal court in Kansas and one matter pending in federal court in California. The Company intends to defend against these lawsuits.
	Governmental Proceedings
	As previously disclosed, on June 21, 2012, the U.S. District Court for the Eastern District of Pennsylvania unsealed a complaint that has been filed against the Company under the federal False Claims Act by two former employees alleging, among other things, that the Company defrauded the U.S. government by falsifying data in connection with a clinical study conducted on the mumps component of the Company’s M-M-R II vaccine. The complaint alleges the fraud took place between 1999 and 2001. The U.S. government had the right to participate in and take over the prosecution of this lawsuit, but has notified the court that it declined to exercise that right. The two former employees are pursuing the lawsuit without the involvement of the U.S. government. In addition, a putative class action lawsuit has been filed against the Company in the Eastern District of Pennsylvania on behalf of direct purchasers of the M-M-R II vaccine which is predicated on the allegations in the False Claims Act complaint and charges that the Company misrepresented the efficacy of the M-M-R II vaccine in violation of federal antitrust laws and various state consumer protection laws. On September 4, 2014, the Court denied Merck’s motion to dismiss the False Claims Act suit and granted in part and denied in part its motion to dismiss the follow-on antitrust suit. As a result, both cases will now proceed into discovery. The Company intends to defend against these lawsuits.
	The Company’s subsidiaries in China have received and may continue to receive inquiries regarding their operations from various Chinese governmental agencies. Some of these inquiries may be related to matters involving other multinational pharmaceutical companies, as well as Chinese entities doing business with such companies. The Company’s policy is to cooperate with these authorities and to provide responses as appropriate.
	Commercial Litigation
	AWP Litigation
	As previously disclosed, the Company and/or certain of its subsidiaries have been named as defendants in various cases alleging manipulation by pharmaceutical manufacturers of Average Wholesale Prices (“AWP”), which are sometimes used by public and private payors in calculating provider reimbursement levels. The Company has reached a settlement in a putative class action in New Jersey Superior Court alleging AWP-related claims on behalf of third-party payers and individuals which was dismissed against the Company without prejudice in 2007 but in which the Company was reinstated as a defendant in 2012. Accordingly, no AWP cases remain pending against the Company.
	Coupon Litigation
	In 2012, as previously disclosed, a number of private health plans filed separate putative class action lawsuits against the Company alleging that Merck’s coupon programs injured health insurers by reducing beneficiary co-payment amounts and, thereby, allegedly causing beneficiaries to purchase higher-priced drugs than they otherwise would have purchased and increasing the insurers’ reimbursement costs. The actions, which were assigned to a District Judge in the U.S. District Court for the District of New Jersey, sought damages and injunctive relief barring the Company from issuing coupons that would reduce beneficiary co-pays on behalf of putative nationwide classes of health insurers. On November 3, 2014, plaintiffs voluntarily dismissed their claims with prejudice.
	Patent Litigation
	From time to time, generic manufacturers of pharmaceutical products file Abbreviated New Drug Applications with the U.S. Food and Drug Administration (the “FDA”) seeking to market generic forms of the Company’s products prior to the expiration of relevant patents owned by the Company. To protect its patent rights, the Company may file patent infringement lawsuits against such generic companies. Certain products of the Company (or products marketed via agreements with other companies) currently involved in such patent infringement litigation in the United States include: Cancidas, Emend for Injection, Invanz, Nasonex, and NuvaRing. Similar lawsuits defending the Company’s patent rights may exist in other countries. The Company intends to vigorously defend its patents, which it believes are valid, against infringement by generic companies attempting to market products prior to the expiration of such patents. As with any litigation, there can be no assurance of the outcomes, which, if adverse, could result in significantly shortened periods of exclusivity for these products and, with respect to products acquired through mergers and acquisitions, potentially significant intangible asset impairment charges.
	Cancidas — In February 2014, a patent infringement lawsuit was filed in the United States against Xellia Pharmaceuticals ApS (“Xellia”) with respect to Xellia’s application to the FDA seeking pre-patent expiry approval to market a generic version of Cancidas. The lawsuit automatically stays FDA approval of Xellia’s application until July 2016 or until an adverse court decision, if any, whichever may occur earlier. In August 2014, a patent infringement lawsuit was filed in the United States against Fresenius Kabi USA, LLC (“Fresenius”) in respect of Fresenius’s application to the FDA seeking pre-patent expiry approval to market a generic version of Cancidas. The lawsuit automatically stays FDA approval of Fresenius’s application until December 2016 or until an adverse court decision, if any, whichever may occur earlier.
	Emend for Injection — In May 2012, a patent infringement lawsuit was filed in the United States against Sandoz Inc. (“Sandoz”) in respect of Sandoz’s application to the FDA seeking pre-patent expiry approval to market a generic version of Emend for Injection. The lawsuit automatically stays FDA approval of Sandoz’s application until July 2015 or until an adverse court decision, if any, whichever may occur earlier. In June 2012, a patent infringement lawsuit was filed in the United States against Accord Healthcare, Inc. US, Accord Healthcare, Inc. and Intas Pharmaceuticals Ltd (collectively, “Intas”) in respect of Intas’ application to the FDA seeking pre-patent expiry approval to market a generic version of Emend for Injection. The Company has agreed with Intas to stay the lawsuit pending the outcome of the lawsuit with Sandoz. In July 2014, a patent infringement lawsuit was filed in the United States against Fresenius in respect of Fresenius’s application to the FDA seeking pre-patent expiry approval to market a generic version of Emend for Injection. The lawsuit automatically stays FDA approval of Fresenius’s application until November 2016 or until an adverse court decision, if any, whichever may occur earlier.
	Invanz — In July 2014, a patent infringement lawsuit was filed in the United States against Hospira Inc. (“Hospira”) in respect of Hospira’s application to the FDA seeking pre-patent expiry approval to market a generic version of Invanz. The lawsuit automatically stays FDA approval of Hospira’s application until November 2016 or until an adverse court decision, if any, whichever may occur earlier. Also in July 2014, a patent infringement lawsuit was filed in the United States against Sandoz in respect of Sandoz’s application to the FDA seeking pre-patent expiry approval to market a generic version of Invanz. As neither Hospira nor Sandoz challenged an earlier patent covering Invanz, both parties’ application to the FDA will not be approved until at least that patent expires in May 2016.
	Nasonex — In July 2014, a patent infringement lawsuit was filed in the United States against Teva Pharmaceuticals USA, Inc. (“Teva”) in respect of Teva’s application to the FDA seeking pre-patent expiry approval to market a generic version of Nasonex. The lawsuit automatically stays FDA approval of Teva’s application until November 2016 or until an adverse court decision, if any, whichever may occur earlier. A decision issued in June 2013 held that the same Merck patent covering mometasone furoate monohydrate was valid, but that it was not infringed by Apotex Corp.’s proposed product.
	NuvaRing — In December 2013, the Company filed a lawsuit against a subsidiary of Actavis plc in the United States in respect of that company’s application to the FDA seeking pre-patent expiry approval to sell a generic version of NuvaRing.
	Anti-PD-1 Antibody Patent Oppositions and Litigation
	As previously disclosed, Ono Pharmaceutical Co. (“Ono”) has a European patent (EP 1 537 878) (“’878”) that broadly claims the use of an anti-PD-1 antibody, such as the Company’s immunotherapy, Keytruda, for the treatment of cancer. Ono has previously licensed its commercial rights to an anti-PD-1 antibody to Bristol-Myers Squibb (“BMS”) in certain markets. The Company believes that the ’878 patent is invalid and filed an opposition in the European Patent Office (the “EPO”) seeking its revocation. In June 2014, the Opposition Division of the EPO found the claims in the ’878 patent are valid. The Company received the Opposition Division’s written opinion in September 2014 and the Company must submit its substantive appeal in February 2015. On April 30, 2014, the Company, and three other companies, opposed another European patent (EP 2 161 336) (“’336”) owned by BMS and Ono that it believes is invalid. The ’336 patent, if valid, broadly claims anti-PD-1 antibodies that could include Keytruda.
	In May 2014, the Company filed a lawsuit in the United Kingdom (“UK”) seeking revocation of the UK national versions of both the ’878 and ’336 patents. In July 2014, Ono and BMS sued the Company seeking a declaration that the ’878 patent would be infringed in the UK by the marketing of Keytruda. The Company has sought a declaration of non-infringement from the UK court that Keytruda will not infringe the ’336 patent in the UK. It is anticipated that the issues of validity and infringement of both patents will be heard at the same time by the UK court, which has scheduled the trial to begin in July 2015.
	The Company can file lawsuits seeking revocation of the ’336 and ’878 patents in other national courts in Europe at any time, and Ono and BMS can file patent infringement actions against the Company in other national courts in Europe at or around the time the Company launches Keytruda (if approved). If a national court determines that the Company infringed a valid claim in the ’878 or ’336 patent, Ono and BMS may be entitled to monetary damages, including royalties on future sales of Keytruda, and potentially could seek an injunction to prevent the Company from marketing Keytruda in that country.
	The United States Patent and Trademark Office granted US Patent Nos. 8,728,474 to Ono and 8,779,105 to Ono and BMS. These patents are equivalent to the ’878 and ’336 patents, respectively. In September 2014, BMS and Ono filed a lawsuit in the United States alleging that, by marketing Keytruda, the Company will infringe US Patent No. 8,728,474. BMS and Ono are not seeking to prevent or stop the marketing of Keytruda in the United States. The Company believes the 8,728,474 patent and the 8,779,105 patent are both invalid.
	In September 2014, the Company filed a lawsuit in Australia, seeking the revocation of Australian Patent No. 2011203119, which is equivalent to the ’336 patent.
	Ono and BMS have similar and other patents and applications, which the Company is closely monitoring, pending in the United States, Japan and other countries.
The Company is confident that it will be able to market Keytruda in any country in which it is approved and that it will not be prevented from doing so by the Ono or BMS patents or any pending applications.
Other Litigation
There are various other pending legal proceedings involving the Company, principally product liability and intellectual property lawsuits. While it is not feasible to predict the outcome of such proceedings, in the opinion of the Company, either the likelihood of loss is remote or any reasonably possible loss associated with the resolution of such proceedings is not expected to be material to the Company’s financial position, results of operations or cash flows either individually or in the aggregate.
Legal Defense Reserves
Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable. Some of the significant factors considered in the review of these legal defense reserves are as follows: the actual costs incurred by the Company; the development of the Company’s legal defense strategy and structure in light of the scope of its litigation; the number of cases being brought against the Company; the costs and outcomes of completed trials and the most current information regarding anticipated timing, progression, and related costs of pre-trial activities and trials in the associated litigation. The amount of legal defense reserves as of September 30, 2014 and December 31, 2013 of approximately $180 million and $160 million, respectively, represents the Company’s best estimate of the minimum amount of defense costs to be incurred in connection with its outstanding litigation; however, events such as additional trials and other events that could arise in the course of its litigation could affect the ultimate amount of legal defense costs to be incurred by the Company. The Company will continue to monitor its legal defense costs and review the adequacy of the associated reserves and may determine to increase the reserves at any time in the future if, based upon the factors set forth, it believes it would be appropriate to do so.

Equity

Equity	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Equity	'
	Equity
					Other			Retained			Accumulated								Non-			Total
		Common Stock			Paid-In			Earnings			Other			Treasury Stock					Controlling
					Capital						Comprehensive								Interests
	($ and shares in millions)	Shares	Par Value								Loss			Shares		Cost
	Balance at January 1, 2013	3,577	$	1,788	$	40,646		$	39,985		$	(4,682	)	550		$	(24,717	)	$	2,443		$	55,463
	Net income attributable to Merck & Co., Inc.	—	—		—			3,623			—			—		—			—			3,623
	Cash dividends declared on common stock	—	—		—			(3,835		)	—			—		—			—			(3,835		)
	Treasury stock shares purchased	—	—		(500		)	—						129		(5,820		)	—			(6,320		)
	Share-based compensation plans and other	—	—		(353		)	—			—			(29	)	1,184			14			845
	Other comprehensive loss	—	—		—			—			(16		)	—					—			(16		)
	Supera joint venture	—	—		116			—			—			—		—			112			228
	Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			79			79
	Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(61		)	(61		)
	Balance at September 30, 2013	3,577	$	1,788	$	39,909		$	39,773		$	(4,698	)	650		$	(29,353	)	$	2,587		$	50,006
	Balance at January 1, 2014	3,577	$	1,788	$	40,508		$	39,257		$	(2,197	)	650		$	(29,591	)	$	2,561		$	52,326
	Net income attributable to Merck & Co., Inc.	—	—		—			4,604			—			—		—			—			4,604
	Cash dividends declared on common stock	—	—		—			(3,872		)	—			—		—			—			(3,872		)
	Treasury stock shares purchased	—	—		—			—			—			106		(6,083		)	—			(6,083		)
	Share-based compensation plans and other	—	—		(168		)	—			—			(40	)	1,779			46			1,657
	Other comprehensive loss	—	—		—			—			(801		)	—		—			—			(801		)
	AstraZeneca option exercise	—	—		—			—			—			—		—			(2,400		)	(2,400		)
	Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			3			3
	Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(74		)	(74		)
	Balance at September 30, 2014	3,577	$	1,788	$	40,340		$	39,989		$	(2,998	)	716		$	(33,895	)	$	136		$	45,360
	On May 20, 2013, Merck entered into an accelerated share repurchase (“ASR”) agreement with Goldman, Sachs & Co. (“Goldman Sachs”). Under the ASR, Merck agreed to purchase $5.0 billion of Merck’s common stock, in total, with an initial delivery of approximately 99.5 million shares of Merck’s common stock, based on current market price, made by Goldman Sachs to Merck, and payment of $5.0 billion made by Merck to Goldman Sachs, on May 21, 2013. The payment to Goldman Sachs was recorded as a reduction to shareholders’ equity, consisting of a $4.5 billion increase in treasury stock, which reflects the value of the initial 99.5 million shares received upon execution, and a $500 million decrease in other-paid-in capital, which reflects the value of the stock held back by Goldman Sachs pending final settlement. Upon settlement of the ASR on October 31, 2013, Merck received an additional 5.5 million shares as determined by the average daily volume weighted-average price of Merck’s common stock during the term of the ASR program bringing the total shares received by Merck under this program to 105 million. The ASR was entered into pursuant to a share repurchase program announced on May 1, 2013.
	In connection with the 1998 restructuring of Astra Merck Inc., the Company assumed $2.4 billion par value preferred stock with a dividend rate of 5% per annum, which was carried by KBI and included in Noncontrolling interests on the Consolidated Balance Sheet. As discussed in Note 7, on June 30, 2014, AstraZeneca exercised its option to acquire Merck’s interest in AZLP and this preferred stock obligation was retired.

ShareBased_Compensation_Plans

Share-Based Compensation Plans	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Share-Based Compensation Plans	'
	Share-Based Compensation Plans
	The Company has share-based compensation plans under which the Company grants restricted stock units (“RSUs”) and performance share units (“PSUs”) to certain management level employees. In addition, employees, non-employee directors and employees of certain of the Company’s equity method investees may be granted options to purchase shares of Company common stock at the fair market value at the time of grant.
	The following table provides amounts of share-based compensation cost recorded in the Consolidated Statement of Income:
		Three Months Ended							Nine Months Ended
		September 30,							September 30,
	($ in millions)	2014				2013			2014			2013
	Pretax share-based compensation expense	$	75			$	68		$	209		$	210
	Income tax benefit	(23		)		(21		)	(64		)	(64		)
	Total share-based compensation expense, net of taxes	$	52			$	47		$	145		$	146
	During the first nine months of 2014 and 2013, the Company granted 5 million RSUs with a weighted-average grant date fair value of $58.15 per RSU and 6 million RSUs with a weighted-average grant date fair value of $45.04 per RSU, respectively.
	During the first nine months of 2014 and 2013, the Company granted 5 million stock options with a weighted-average exercise price of $58.15 per option and 6 million stock options with a weighted-average exercise price of $45.00 per option, respectively. The weighted-average fair value of options granted for the first nine months of 2014 and 2013 was $6.79 and $6.21 per option, respectively, and was determined using the following assumptions:
		Nine Months Ended
		September 30, 2014
		2014			2013
	Expected dividend yield	4.3	%		4.2	%
	Risk-free interest rate	2	%		1.2	%
	Expected volatility	22	%		25	%
	Expected life (years)	6.4			7
	At September 30, 2014, there was $502 million of total pretax unrecognized compensation expense related to nonvested stock options, RSU and PSU awards which will be recognized over a weighted-average period of 1.9 years. For segment reporting, share-based compensation costs are unallocated expenses.

Pension_and_Other_Postretireme

Pension and Other Postretirement Benefit Plans	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Pension and Other Postretirement Benefit Plans	'
	Pension and Other Postretirement Benefit Plans
	The Company has defined benefit pension plans covering eligible employees in the United States and in certain of its international subsidiaries. The net periodic benefit cost of such plans consisted of the following components:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Service cost	$	128		$	167		$	428		$	512
	Interest cost	173			166			524			497
	Expected return on plan assets	(300		)	(270		)	(901		)	(817		)
	Net amortization	41			86			96			252
	Termination benefits	16			5			47			10
	Curtailments	(17		)	(4		)	(49		)	(6		)
	Settlements	8			—			8			—
		$	49		$	150		$	153		$	448
	The Company provides medical benefits, principally to its eligible U.S. retirees and similar benefits to their dependents, through its other postretirement benefit plans. The net cost of such plans consisted of the following components:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Service cost	$	18		$	28		$	56		$	76
	Interest cost	27			25			84			79
	Expected return on plan assets	(35		)	(31		)	(104		)	(94		)
	Net amortization	(18		)	(13		)	(53		)	(37		)
	Termination benefits	5			4			13			6
	Curtailments	(7		)	(5		)	(33		)	(7		)
		$	(10	)	$	8		$	(37	)	$	23
	In connection with restructuring actions (see Note 2), termination charges were recorded on pension and other postretirement benefit plans related to expanded eligibility for certain employees exiting Merck. Also, in connection with these restructuring actions, curtailments were recorded on pension and other postretirement benefit plans as reflected in the tables above.

Other_Income_Expense_Net

Other (Income) Expense, Net	9 Months Ended
	Sep. 30, 2014
Other Income and Expenses [Abstract]	'
Other (Income) Expense, Net	'
	Other (Income) Expense, Net
	Other (income) expense, net, consisted of:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Interest income	$	(69	)	$	(67	)	$	(190	)	$	(189	)
	Interest expense	191			215			567			600
	Exchange losses	61			11			114			278
	Other, net	(325		)	13			(1,228		)	(33		)
		$	(142	)	$	172		$	(737	)	$	656
	The lower exchange losses in the first nine months of 2014 as compared with the first nine months of 2013 are due primarily to a Venezuelan currency devaluation. In February 2013, the Venezuelan government devalued its currency (Bolívar Fuertes) from 4.30 VEF per U.S. dollar to 6.30 VEF per U.S. dollar. The Company recognized losses due to exchange of approximately $140 million in the first quarter of 2013 resulting from the remeasurement of the local monetary assets and liabilities at the new rate. Since January 2010, Venezuela has been designated hyperinflationary and, as a result, local foreign operations are remeasured in U.S. dollars with the impact recorded in results of operations. Other net, in the third quarter and first nine months of 2014 includes a $396 million gain on the divestiture of certain ophthalmic products in several international markets to Santen (see Note 3), partially offset by a $93 million goodwill impairment charge related to the Company’s joint venture with Supera (see Note 3). Other, net in the first nine months of 2014 also includes a gain of $741 million related to AstraZeneca’s option exercise (see Note 7) and a net gain of $168 million related to the divestiture of Sirna (see Note 3).
	Interest paid for the nine months ended September 30, 2014 and 2013 was $544 million and $562 million, respectively.

Taxes_on_Income

Taxes on Income	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Taxes on Income	'
	Taxes on Income
	The effective income tax rates of 43.5% and 24.6% for the third quarter of 2014 and 2013, respectively, and 15.8% and 14.3% for the first nine months of 2014 and 2013, respectively, reflect the impacts of acquisition-related costs and restructuring costs, partially offset by the beneficial impact of foreign earnings. The effective income tax rates for the third quarter and first nine months of 2014 include the unfavorable impact of an additional year of expense for the non-tax deductible health care reform fee that the Company recorded in accordance with final regulations issued in the third quarter by the Internal Revenue Service (the “IRS”). In addition, the effective income tax rate for the first nine months of 2014 includes a net tax benefit of $517 million recorded in connection with AstraZeneca’s option exercise (see Note 7) and a benefit of approximately $300 million associated with a capital loss generated in the first quarter related to the sale of Sirna (see Note 3). The effective income tax rates for the third quarter and first nine months of 2013 also reflect a net benefit of $165 million from the settlements of certain federal income tax issues as discussed below. Additionally, the effective income tax rate for the first nine months of 2013 reflects net benefits from reductions in tax reserves upon expiration of applicable statute of limitations, the favorable impact of tax legislation enacted in the first quarter of 2013 that extended the R&D tax credit for both 2012 and 2013, as well as a benefit of approximately $160 million associated with the resolution of a previously disclosed federal income tax issue as discussed below.
	In the third quarter of 2013, the IRS finalized its examination of Schering-Plough’s 2007-2009 tax years. The Company’s unrecognized tax benefits for the years under examination exceeded the adjustments related to this examination period and therefore the Company recorded a net $165 million tax provision benefit for the third quarter and first nine months of 2013.
	In 2010, the IRS finalized its examination of Schering-Plough’s 2003-2006 tax years. In this audit cycle, the Company reached an agreement with the IRS on an adjustment to income related to intercompany pricing matters. This income adjustment mostly reduced net operating loss carryforwards and other tax credit carryforwards. The Company’s reserves for uncertain tax positions were adequate to cover all adjustments related to this examination period. Additionally, as previously disclosed, the Company was seeking resolution of one issue raised during this examination through the IRS administrative appeals process. In the first quarter of 2013, the Company recorded an out-of-period net tax benefit of $160 million related to this issue, which was settled in the fourth quarter of 2012, with final resolution relating to interest owed being reached in the first quarter of 2013. The Company’s unrecognized tax benefits related to this issue exceeded the settlement amount. Management concluded that the exclusion of this benefit was not material to prior period financial statements.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	The calculations of earnings per share are as follows:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
	($ and shares in millions except per share amounts)	2014		2013		2014		2013
	Net income attributable to Merck & Co., Inc.	$	895	$	1,124	$	4,604	$	3,623
	Average common shares outstanding	2,879		2,927		2,909		2,975
	Common shares issuable (1)	32		33		33		32
	Average common shares outstanding assuming dilution	2,911		2,960		2,942		3,007
	Basic earnings per common share attributable to Merck & Co., Inc. common shareholders	$	0.31	$	0.38	$	1.58	$	1.22
	Earnings per common share assuming dilution attributable to Merck & Co., Inc. common shareholders	$	0.31	$	0.38	$	1.57	$	1.2
	(1)	Issuable primarily under share-based compensation plans.
	For the three months ended September 30, 2014 and 2013, 5 million and 23 million, respectively, and for the first nine months of 2014 and 2013, 4 million and 29 million, respectively, of common shares issuable under share-based compensation plans were excluded from the computation of earnings per common share assuming dilution because the effect would have been antidilutive.

Other_Comprehensive_Income_Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Other Comprehensive Income (Loss)	'
	Other Comprehensive Income (Loss)
	Changes in AOCI by component are as follows:
		Three Months Ended September 30,
	($ in millions)	Derivatives				Investments				Employee				Cumulative			Accumulated Other
										Benefit				Translation			Comprehensive
										Plans				Adjustment			Income (Loss)
	Balance July 1, 2013, net of taxes	$	174			$	(7	)		$	(3,455	)		$	(1,472	)	$	(4,760	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	(165		)		55				(7		)		74			(43		)
	Tax	63				(8		)		—				(2		)	53
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	(102		)		47				(7		)		72			10
	Reclassification adjustments, pretax	—				(9		)		73				—			64
	Tax	—				5				(17		)		—			(12		)
	Reclassification adjustments, net of taxes	—			(1)	(4		)	(2)	56			(3)	—			52
	Other comprehensive income (loss), net of taxes	(102		)		43				49				72			62
	Balance September 30, 2013, net of taxes	$	72			$	36			$	(3,406	)		$	(1,400	)	$	(4,698	)
	Balance July 1, 2014, net of taxes	$	27			$	116			$	(1,241	)		$	(1,346	)	$	(2,444	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	434				(26		)		(715		)		(244		)	(551		)
	Tax	(152		)		(7		)		226				(72		)	(5		)
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	282				(33		)		(489		)		(316		)	(556		)
	Reclassification adjustments, pretax	(44		)		5				34				—			(5		)
	Tax	16				(1		)		(8		)		—			7
	Reclassification adjustments, net of taxes	(28		)	(1)	4			(2)	26			(3)	—			2
	Other comprehensive income (loss), net of taxes	254				(29		)		(463		)		(316		)	(554		)
	Balance September 30, 2014, net of taxes	$	281			$	87			$	(1,704	)		$	(1,662	)	$	(2,998	)
		Nine Months Ended September 30,
	($ in millions)	Derivatives				Investments				Employee				Cumulative			Accumulated Other
										Benefit				Translation			Comprehensive
										Plans				Adjustment			Income (Loss)
	Balance January 1, 2013, net of taxes	$	(97	)		$	73			$	(3,667	)		$	(991	)	$	(4,682	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	248				11				137				(304		)	92
	Tax	(100		)		(16		)		(30		)		(105		)	(251		)
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	148				(5		)		107				(409		)	(159		)
	Reclassification adjustments, pretax	33				(43		)		215				—			205
	Tax	(12		)		11				(61		)		—			(62		)
	Reclassification adjustments, net of taxes	21			(1)	(32		)	(2)	154			(3)	—			143
	Other comprehensive income (loss), net of taxes	169				(37		)		261				(409		)	(16		)
	Balance September 30, 2013, net of taxes	$	72			$	36			$	(3,406	)		$	(1,400	)	$	(4,698	)
	Balance January 1, 2014, net of taxes	$	132			$	54			$	(909	)		$	(1,474	)	$	(2,197	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	277				13				(1,287		)		(123		)	(1,120		)
	Tax	(97		)		(2		)		449				(65		)	285
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	180				11				(838		)		(188		)	(835		)
	Reclassification adjustments, pretax	(48		)		35				54				—			41
	Tax	17				(13		)		(11		)		—			(7		)
	Reclassification adjustments, net of taxes	(31		)	(1)	22			(2)	43			(3)	—			34
	Other comprehensive income (loss), net of taxes	149				33				(795		)		(188		)	(801		)
	Balance September 30, 2014, net of taxes	$	281			$	87			$	(1,704	)		$	(1,662	)	$	(2,998	)
	(1) Relates to foreign currency cash flow hedges that were reclassified from AOCI to Sales.
	(2) Represents net realized (gains) losses on the sales of available-for-sale investments that were reclassified from AOCI to Other (income) expense, net.
	(3) Includes net amortization of prior service cost and actuarial gains and losses included in net periodic benefit cost (see Note 12).

Segment_Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	Segment Reporting
	The Company’s operations are principally managed on a products basis and include the Pharmaceutical, Animal Health, Alliances (which includes revenue and equity income from the Company’s relationship with AZLP until the June 30, 2014 termination date) and Consumer Care (until its divestiture on October 1, 2014) operating segments. The Animal Health, Consumer Care and Alliances segments are not material for separate reporting. The Pharmaceutical segment includes human health pharmaceutical and vaccine products marketed either directly by the Company or through joint ventures. Human health pharmaceutical products consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. The Company sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies and managed health care providers such as health maintenance organizations, pharmacy benefit managers and other institutions. Vaccine products consist of preventive pediatric, adolescent and adult vaccines, primarily administered at physician offices. The Company sells these human health vaccines primarily to physicians, wholesalers, physician distributors and government entities. A large component of pediatric and adolescent vaccines is sold to the U.S. Centers for Disease Control and Prevention Vaccines for Children program, which is funded by the U.S. government. Additionally, the Company sells vaccines to the Federal government for placement into vaccine stockpiles. The Company also has animal health operations that discover, develop, manufacture and market animal health products, including vaccines, which the Company sells to veterinarians, distributors and animal producers. On October 1, 2014, the Company sold its Consumer Care business that developed, manufactured and marketed over-the-counter, foot care and sun care products (see Note 3).
	Sales of the Company’s products were as follows:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Primary Care and Women’s Health
	Cardiovascular
	Zetia	$	660		$	662		$	1,988		$	1,941
	Vytorin	369			396			1,146			1,207
	Diabetes
	Januvia/Janumet	1,439			1,369			4,350			4,208
	General Medicine and Women’s Health
	NuvaRing	186			170			531			492
	Implanon/Nexplanon	158			96			379			282
	Dulera	124			82			328			229
	Follistim AQ	97			124			309			380
	Hospital and Specialty
	Hepatitis
	PegIntron	84			104			300			372
	Victrelis	27			121			132			347
	HIV
	Isentress	412			427			1,255			1,201
	Acute Care
	Cancidas	183			151			505			477
	Invanz	141			130			390			360
	Noxafil	107			75			280			212
	Bridion	90			75			245			206
	Primaxin	91			88			243			256
	Immunology
	Remicade	604			574			1,815			1,651
	Simponi	170			126			500			354
	Other
	Cosopt/Trusopt	34			104			232			313
	Oncology
	Emend	136			123			402			373
	Temodar	88			162			264			596
	Diversified Brands
	Respiratory
	Nasonex	261			297			830			1,008
	Singulair	218			280			773			898
	Clarinex	49			54			180			180
	Other
	Cozaar/Hyzaar	195			238			614			760
	Arcoxia	132			112			400			354
	Fosamax	114			140			358			421
	Propecia	66			71			197			206
	Zocor	61			65			194			221
	Remeron	47			44			137			150
	Vaccines (1)
	Gardasil	590			665			1,382			1,438
	ProQuad/M-M-R II/Varivax	421			421			1,027			1,032
	RotaTeq	174			201			490			507
	Zostavax	181			185			479			494
	Pneumovax 23	197			193			400			412
	Other pharmaceutical (2)	1,228			1,350			3,617			4,139
	Total Pharmaceutical segment sales	9,134			9,475			26,672			27,677
	Other segment sales (3)	1,321			1,501			4,657			4,844
	Total segment sales	10,455			10,976			31,329			32,521
	Other (4)	102			56			426			192
		$	10,557		$	11,032		$	31,755		$	32,713
	(1)	These amounts do not reflect sales of vaccines sold in most major European markets through the Company’s joint venture, Sanofi Pasteur MSD, the results of which are reflected in Equity income from affiliates. These amounts do, however, reflect supply sales to Sanofi Pasteur MSD.
	(2)	Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately.
(3)	Represents the non-reportable segments of Animal Health, Consumer Care and Alliances. The Alliances segment includes revenue from the Company’s relationship with AZLP until its termination on June 30, 2014 (see Note 7). On October 1, 2014, the Company sold its Consumer Care business to Bayer (see Note 3).
(4)	Other revenues are primarily comprised of miscellaneous corporate revenues, sales related to divested products or businesses, and other supply sales not included in segment results. Other revenues in the first nine months of 2014 include $232 million received by Merck in connection with the sale of the U.S. marketing rights to Saphris (see Note 3). Other revenues also include third-party manufacturing sales, a substantial portion of which was divested in October 2013 (see Note 2).
A reconciliation of segment profits to Income before taxes is as follows:
	Three Months Ended						Nine Months Ended
	September 30,						September 30,
($ in millions)	2014			2013			2014			2013
Segment profits:
Pharmaceutical segment	$	5,772		$	5,983		$	16,475		$	17,022
Other segments	539			750			2,050			2,445
Total segment profits	6,311			6,733			18,525			19,467
Other profits (losses)	79			(6		)	370			(24		)
Unallocated:
Interest income	69			67			190			189
Interest expense	(191		)	(215		)	(567		)	(600		)
Equity income from affiliates	(22		)	(67		)	62			(82		)
Depreciation and amortization	(595		)	(512		)	(1,895		)	(1,449		)
Research and development	(1,332		)	(1,419		)	(3,984		)	(4,928		)
Amortization of purchase accounting adjustments	(1,008		)	(1,176		)	(3,198		)	(3,545		)
Restructuring costs	(376		)	(870		)	(664		)	(1,144		)
AstraZeneca option exercise	—			—			741			—
Gain on divestiture of certain ophthalmic products	396			—			396			—
Other unallocated, net	(1,841		)	(1,010		)	(4,504		)	(3,564		)
	$	1,490		$	1,525		$	5,472		$	4,320
Segment profits are comprised of segment sales less standard costs and certain operating expenses directly incurred by the segments. For internal management reporting presented to the chief operating decision maker, Merck does not allocate materials and production costs, other than standard costs, the majority of research and development expenses or general and administrative expenses, nor the cost of financing these activities. Separate divisions maintain responsibility for monitoring and managing these costs, including depreciation related to fixed assets utilized by these divisions and, therefore, they are not included in segment profits. In addition, costs related to restructuring activities, as well as the amortization of purchase accounting adjustments are not allocated to segments.
Other profits (losses) are primarily comprised of miscellaneous corporate profits (losses), as well as operating profits (losses) related to third-party manufacturing sales, divested products and other supply sales.
Other unallocated, net includes expenses from corporate and manufacturing cost centers, goodwill and product intangible asset impairment charges, gains or losses on sales of businesses and other miscellaneous income or expense items.

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Recently Issued Accounting Standards	'
	In May 2014, the Financial Accounting Standards Board issued amended accounting guidance on revenue recognition that will be applied to all contracts with customers. The objective of the new guidance is to improve comparability of revenue recognition practices across entities and to provide more useful information to users of financial statements through improved disclosure requirements. This guidance is effective for annual and interim periods beginning in 2017. Early adoption is not permitted. The Company is currently assessing the impact of adoption on its consolidated financial statements.
Legal Costs, Policy	'
	Legal defense costs expected to be incurred in connection with a loss contingency are accrued when probable and reasonably estimable.

Restructuring_Tables

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2014
Restructuring and Related Activities [Abstract]	'
Charges Related to Restructuring Program Activities by Type of Cost	'
	The following tables summarize the charges related to restructuring program activities by type of cost:
		Three Months Ended September 30, 2014												Nine Months Ended September 30, 2014
	($ in millions)	Separation			Accelerated			Other			Total			Separation		Accelerated			Other			Total
		Costs			Depreciation									Costs		Depreciation
	2013 Restructuring Program
	Materials and production	$	—		$	5		$	—		$	5		$	—	$	189		$	17		$	206
	Marketing and administrative	—			45			—			45			—		92			—			92
	Research and development	—			75			6			81			—		160			14			174
	Restructuring costs	310			—			(4		)	306			387		—			(33		)	354
		310			125			2			437			387		441			(2		)	826
	Merger Restructuring Program
	Materials and production	—			67			15			82			—		219			(48		)	171
	Marketing and administrative	—			29			(6		)	23			—		54			(3		)	51
	Research and development	—			—			—			—			—		—			1			1
	Restructuring costs	5			—			65			70			104		—			206			310
		5			96			74			175			104		273			156			533
		$	315		$	221		$	76		$	612		$	491	$	714		$	154		$	1,359
		Three Months Ended September 30, 2013												Nine Months Ended September 30, 2013
	($ in millions)	Separation			Accelerated			Other			Total			Separation		Accelerated			Other			Total
		Costs			Depreciation									Costs		Depreciation
	2013 Restructuring Program
	Materials and production	$	—		$	20		$	—		$	20		$	—	$	20		$	—		$	20
	Marketing and administrative	—			15			—			15			—		15			—			15
	Research and development	—			8			—			8			—		8			—			8
	Restructuring costs	501			—			—			501			501		—			—			501
		501			43			—			544			501		43			—			544
	Merger Restructuring Program
	Materials and production	—			30			7			37			—		91			78			169
	Marketing and administrative	—			20			(4		)	16			—		44			1			45
	Research and development	—			1			—			1			—		30			—			30
	Restructuring costs	241			—			128			369			435		—			162			597
		241			51			131			423			435		165			241			841
	2008 Restructuring Program
	Materials and production	—			—			—			—			—		(2		)	6			4
	Marketing and administrative	—			—			—			—			—		4			—			4
	Restructuring costs	—			—			—			—			34		—			12			46
		—			—			—			—			34		2			18			54
		$	742		$	94		$	131		$	967		$	970	$	210		$	259		$	1,439
Charges and Spending Relating to Restructuring Activities by Program	'
	The following table summarizes the charges and spending relating to restructuring activities by program for the nine months ended September 30, 2014:
	($ in millions)	Separation			Accelerated			Other			Total
		Costs			Depreciation
	2013 Restructuring Program
	Restructuring reserves January 1, 2014	$	745		$	—		$	23		$	768
	Expense	387			441			(2		)	826
	(Payments) receipts, net	(596		)	—			(46		)	(642		)
	Non-cash activity	—			(441		)	43			(398		)
	Restructuring reserves September 30, 2014 (1)	$	536		$	—		$	18		$	554
	Merger Restructuring Program
	Restructuring reserves January 1, 2014	$	725		$	—		$	12		$	737
	Expense	104			273			156			533
	(Payments) receipts, net	(237		)	—			(171		)	(408		)
	Non-cash activity	—			(273		)	10			(263		)
	Restructuring reserves September 30, 2014 (1)	$	592		$	—		$	7		$	599
	(1)	The cash outlays associated with the 2013 Restructuring Program are expected to be substantially completed by the end of 2015. The non-manufacturing cash outlays associated with the Merger Restructuring Program were substantially completed by the end of 2013; the remaining cash outlays are expected to be substantially completed by 2016.

Acquisitions_Divestitures_Rese1

Acquisitions, Divestitures, Research Collaborations and License Agreements (Tables)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Schedule of Assets and Liabilities of Merck Consumer Care Classified as Held for Sale	'
	Information with respect to Consumer Care assets and liabilities held for sale at September 30 is as follows:
	($ millions)	30-Sep-14
	Assets
	Accounts receivable, net	$	79
	Inventories	278
	Deferred income taxes and other current assets	25
	Property, plant and equipment, net	212
	Goodwill	162
	Other intangibles, net	2,194
	Other assets	56
		$	3,006
	Liabilities
	Trade accounts payable	$	84
	Accrued and other current liabilities	114
	Deferred income taxes	561
	Other noncurrent liabilities	6
		$	765

Financial_Instruments_Tables

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Fair Value of Derivatives on a Gross Basis Segregated between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments	'
	Presented in the table below is the fair value of derivatives on a gross basis segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments:
			30-Sep-14									31-Dec-13
			Fair Value of Derivative						U.S. Dollar			Fair Value of Derivative						U.S. Dollar
	($ in millions)	Balance Sheet Caption	Asset			Liability			Notional			Asset			Liability			Notional
	Derivatives Designated as Hedging Instruments
	Interest rate swap contracts (non-current)	Other assets	$	8		$	—		$	550		$	13		$	—		$	1,550
	Interest rate swap contracts (non-current)	Other noncurrent liabilities	—			22			2,000			—			25			2,000
	Foreign exchange contracts (current)	Deferred income taxes and other current assets	627			—			7,157			493			—			4,427
	Foreign exchange contracts (non-current)	Other assets	491			—			6,238			515			—			6,676
	Foreign exchange contracts (current)	Accrued and other current liabilities	—			1			464			—			19			1,659
	Foreign exchange contracts (non-current)	Other noncurrent liabilities	—			1			120			—			—			—
			$	1,126		$	24		$	16,529		$	1,021		$	44		$	16,312
	Derivatives Not Designated as Hedging Instruments
	Foreign exchange contracts (current)	Deferred income taxes and other current assets	$	234		$	—		$	9,192		$	69		$	—		$	5,705
	Foreign exchange contracts (current)	Accrued and other current liabilities	—			70			4,687			—			140			7,892
			$	234		$	70		$	13,879		$	69		$	140		$	13,597
			$	1,360		$	94		$	30,408		$	1,090		$	184		$	29,909
Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis	'
	The following table provides information on the Company’s derivative positions subject to these master netting arrangements as if they were presented on a net basis, allowing for the right of offset by counterparty and cash collateral exchanged per the master agreements and related credit support annexes:
		30-Sep-14						31-Dec-13
	($ in millions)	Asset			Liability			Asset			Liability
	Gross amounts recognized in the consolidated balance sheet	$	1,360		$	94		$	1,090		$	184
	Gross amount subject to offset in master netting arrangements	(91		)	(91		)	(147		)	(147		)
	not offset in the consolidated balance sheet
	Cash collateral (received) posted	(942		)	—			(652		)	—
	Net amounts	$	327		$	3		$	291		$	37
Location and Pretax Gain or Loss Amounts for Derivatives that are: (i) Designated in a Fair Value Hedging Relationship, (ii) Designated in a Cash Flow Hedging Relationship, (iii) Designated in a Foreign Currency net Investment Hedging Relationship and (iv) Not Designated in a Hedging Relationship	'
	The table below provides information on the location and pretax gain or loss amounts for derivatives that are: (i) designated in a fair value hedging relationship, (ii) designated in a foreign currency cash flow hedging relationship, (iii) designated in a foreign currency net investment hedging relationship and (iv) not designated in a hedging relationship:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Derivatives designated in a fair value hedging relationship
	Interest rate swap contracts
	Amount of loss (gain) recognized in Other (income) expense, net on derivatives (1)	$	23		$	(33	)	$	2		$	1
	Amount of (gain) loss recognized in Other (income) expense, net on hedged item	(23		)	30			(3		)	(2		)
	Derivatives designated in foreign currency cash flow hedging relationships
	Foreign exchange contracts
	Amount of (gain) loss reclassified from AOCI to Sales	(42		)	1			(45		)	36
	Amount of (gain) loss recognized in OCI on derivatives	(433		)	165			(276		)	(219		)
	Derivatives designated in foreign currency net investment hedging relationships
	Foreign exchange contracts
	Amount of gain recognized in Other (income) expense, net on derivatives (2)	(1		)	(5		)	(3		)	(7		)
	Amount of gain recognized in OCI on derivatives	(116		)	(15		)	(67		)	(259		)
	Derivatives not designated in a hedging relationship
	Foreign exchange contracts
	Amount of (gain) loss recognized in Other (income) expense, net on derivatives (3)	(290		)	154			(314		)	146
	Amount of loss recognized in Sales	5			8			5			5
	(1) There was $3 million of ineffectiveness on the hedge during the third quarter and first nine months of 2013.
	(2) There was no ineffectiveness on the hedge. Represents the amount excluded from hedge effectiveness testing.
	(3) These derivative contracts mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.
Information on Available-for-sale Investments	'
	Information on available-for-sale investments is as follows:
		30-Sep-14												31-Dec-13
		Fair			Amortized			Gross Unrealized						Fair			Amortized			Gross Unrealized
	($ in millions)	Value			Cost			Gains			Losses			Value			Cost			Gains		Losses
	Corporate notes and bonds	$	9,428		$	9,411		$	31		$	(14	)	$	7,054		$	7,037		$	32	$	(15	)
	Commercial paper	2,121			2,121			—			—			1,206			1,206			—		—
	U.S. government and agency securities	2,039			2,042			—			(3		)	1,236			1,239			1		(4		)
	Asset-backed securities	1,440			1,441			1			(2		)	1,300			1,303			1		(4		)
	Mortgage-backed securities	538			540			1			(3		)	476			479			2		(5		)
	Foreign government bonds	456			456			—			—			125			126			—		(1		)
	Equity securities	707			589			118			—			471			397			74		—
		$	16,729		$	16,600		$	151		$	(22	)	$	11,868		$	11,787		$	110	$	(29	)
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	'
	Financial assets and liabilities measured at fair value on a recurring basis are summarized below:
		Fair Value Measurements Using												Fair Value Measurements Using
		Quoted Prices			Significant			Significant			Total			Quoted Prices			Significant			Significant		Total
		In Active			Other			Unobservable						In Active			Other			Unobservable
		Markets for			Observable			Inputs						Markets for			Observable			Inputs
		Identical Assets			Inputs			(Level 3)						Identical Assets			Inputs			(Level 3)
		(Level 1)			(Level 2)									(Level 1)			(Level 2)
	($ in millions)	30-Sep-14												31-Dec-13
	Assets
	Investments
	Corporate notes and bonds	$	—		$	9,428		$	—		$	9,428		$	—		$	7,054		$	—	$	7,054
	Commercial paper	—			2,121			—			2,121			—			1,206			—		1,206
	U.S. government and agency securities	—			2,039			—			2,039			—			1,236			—		1,236
	Asset-backed securities (1)	—			1,440			—			1,440			—			1,300			—		1,300
	Mortgage-backed securities (1)	—			538			—			538			—			476			—		476
	Foreign government bonds	—			456			—			456			—			125			—		125
	Equity securities	447			—			—			447			238			—			—		238
		447			16,022			—			16,469			238			11,397			—		11,635
	Other assets
	Securities held for employee compensation	198			62			—			260			186			47			—		233
	Derivative assets (2)
	Purchased currency options	—			918			—			918			—			868			—		868
	Forward exchange contracts	—			434			—			434			—			209			—		209
	Interest rate swaps	—			8			—			8			—			13			—		13
		—			1,360			—			1,360			—			1,090			—		1,090
	Total assets	$	645		$	17,444		$	—		$	18,089		$	424		$	12,534		$	—	$	12,958
	Liabilities
	Derivative liabilities (2)
	Forward exchange contracts	$	—		$	29		$	—		$	29		$	—		$	134		$	—	$	134
	Written currency options	—			43			—			43			—			25			—		25
	Interest rate swaps	—			22			—			22			—			25			—		25
	Total liabilities	$	—		$	94		$	—		$	94		$	—		$	184		$	—	$	184
	(1)	Primarily all of the asset-backed securities are highly-rated (Standard & Poor’s rating of AAA and Moody’s Investors Service rating of Aaa), secured primarily by credit card, auto loan, and home equity receivables, with weighted-average lives of primarily 5 years or less. Mortgage-backed securities represent AAA-rated securities issued or unconditionally guaranteed as to payment of principal and interest by U.S. government agencies.
	(2)	The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Sep. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	Inventories consisted of:
	($ in millions)	30-Sep-14		31-Dec-13
	Finished goods	$	1,811	$	1,738
	Raw materials and work in process	5,350		5,894
	Supplies	212		225
	Total (approximates current cost)	7,373		7,857
	Increase to LIFO costs	220		73
		$	7,593	$	7,930
	Recognized as:
	Inventories	$	5,819	$	6,226
	Other assets	1,774		1,704

Joint_Ventures_and_Other_Equit1

Joint Ventures and Other Equity Method Affiliates (Tables)	9 Months Ended
	Sep. 30, 2014
Equity Method Investments and Joint Ventures [Abstract]	'
Equity Income from Affiliates	'
	Equity income from affiliates reflects the performance of the Company’s joint ventures and other equity method affiliates and was comprised of the following:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
	($ in millions)	2014		2013		2014		2013
	AstraZeneca LP (1)	$	—	$	72	$	192	$	302
	Other (2)	24		30		49		49
		$	24	$	102	$	241	$	351
	(1)	As noted below, as of July 1, 2014, the Company no longer records equity income from AZLP.
	(2) Includes results from Sanofi Pasteur MSD.
Summarized Financial Information for AZLP	'
	Summarized financial information for AZLP is as follows:
		Six Months Ended		Three Months Ended September 30,		Nine Months Ended
		June 30,				September 30,
	($ in millions)	2014		2013		2013
	Sales	$	2,205	$	1,083	$	3,383
	Materials and production costs	1,044		554		1,681
	Other expense, net	604		398		1,198
	Income before taxes (1)	$	557	$	131	$	504
	(1)	Merck’s partnership returns from AZLP were generally contractually determined as noted above and were not based on a percentage of income from AZLP, other than with respect to Merck’s 1% limited partnership interest.

Equity_Tables

Equity (Tables)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Shareholders' Equity	'
					Other			Retained			Accumulated								Non-			Total
		Common Stock			Paid-In			Earnings			Other			Treasury Stock					Controlling
					Capital						Comprehensive								Interests
	($ and shares in millions)	Shares	Par Value								Loss			Shares		Cost
	Balance at January 1, 2013	3,577	$	1,788	$	40,646		$	39,985		$	(4,682	)	550		$	(24,717	)	$	2,443		$	55,463
	Net income attributable to Merck & Co., Inc.	—	—		—			3,623			—			—		—			—			3,623
	Cash dividends declared on common stock	—	—		—			(3,835		)	—			—		—			—			(3,835		)
	Treasury stock shares purchased	—	—		(500		)	—						129		(5,820		)	—			(6,320		)
	Share-based compensation plans and other	—	—		(353		)	—			—			(29	)	1,184			14			845
	Other comprehensive loss	—	—		—			—			(16		)	—					—			(16		)
	Supera joint venture	—	—		116			—			—			—		—			112			228
	Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			79			79
	Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(61		)	(61		)
	Balance at September 30, 2013	3,577	$	1,788	$	39,909		$	39,773		$	(4,698	)	650		$	(29,353	)	$	2,587		$	50,006
	Balance at January 1, 2014	3,577	$	1,788	$	40,508		$	39,257		$	(2,197	)	650		$	(29,591	)	$	2,561		$	52,326
	Net income attributable to Merck & Co., Inc.	—	—		—			4,604			—			—		—			—			4,604
	Cash dividends declared on common stock	—	—		—			(3,872		)	—			—		—			—			(3,872		)
	Treasury stock shares purchased	—	—		—			—			—			106		(6,083		)	—			(6,083		)
	Share-based compensation plans and other	—	—		(168		)	—			—			(40	)	1,779			46			1,657
	Other comprehensive loss	—	—		—			—			(801		)	—		—			—			(801		)
	AstraZeneca option exercise	—	—		—			—			—			—		—			(2,400		)	(2,400		)
	Net income attributable to noncontrolling interests	—	—		—			—			—			—		—			3			3
	Distributions attributable to noncontrolling interests	—	—		—			—			—			—		—			(74		)	(74		)
	Balance at September 30, 2014	3,577	$	1,788	$	40,340		$	39,989		$	(2,998	)	716		$	(33,895	)	$	136		$	45,360

ShareBased_Compensation_Plans_

Share-Based Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Amounts of Share-Based Compensation Cost Recorded in Consolidated Statement of Income	'
	The following table provides amounts of share-based compensation cost recorded in the Consolidated Statement of Income:
		Three Months Ended							Nine Months Ended
		September 30,							September 30,
	($ in millions)	2014				2013			2014			2013
	Pretax share-based compensation expense	$	75			$	68		$	209		$	210
	Income tax benefit	(23		)		(21		)	(64		)	(64		)
	Total share-based compensation expense, net of taxes	$	52			$	47		$	145		$	146
Assumptions Used to Determine Weighted-Average Fair Value of Options Granted	'
	The weighted-average fair value of options granted for the first nine months of 2014 and 2013 was $6.79 and $6.21 per option, respectively, and was determined using the following assumptions:
		Nine Months Ended
		September 30, 2014
		2014			2013
	Expected dividend yield	4.3	%		4.2	%
	Risk-free interest rate	2	%		1.2	%
	Expected volatility	22	%		25	%
	Expected life (years)	6.4			7

Pension_and_Other_Postretireme1

Pension and Other Postretirement Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2014
Pension Plans, Defined Benefit [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Components of Net Cost of Defined Benefit Plans	'
	The Company has defined benefit pension plans covering eligible employees in the United States and in certain of its international subsidiaries. The net periodic benefit cost of such plans consisted of the following components:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Service cost	$	128		$	167		$	428		$	512
	Interest cost	173			166			524			497
	Expected return on plan assets	(300		)	(270		)	(901		)	(817		)
	Net amortization	41			86			96			252
	Termination benefits	16			5			47			10
	Curtailments	(17		)	(4		)	(49		)	(6		)
	Settlements	8			—			8			—
		$	49		$	150		$	153		$	448
Other Postretirement Benefit Plans, Defined Benefit [Member]	'
Defined Benefit Plan Disclosure [Line Items]	'
Components of Net Cost of Defined Benefit Plans	'
	The Company provides medical benefits, principally to its eligible U.S. retirees and similar benefits to their dependents, through its other postretirement benefit plans. The net cost of such plans consisted of the following components:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Service cost	$	18		$	28		$	56		$	76
	Interest cost	27			25			84			79
	Expected return on plan assets	(35		)	(31		)	(104		)	(94		)
	Net amortization	(18		)	(13		)	(53		)	(37		)
	Termination benefits	5			4			13			6
	Curtailments	(7		)	(5		)	(33		)	(7		)
		$	(10	)	$	8		$	(37	)	$	23

Other_Income_Expense_Net_Table

Other (Income) Expense, Net (Tables)	9 Months Ended
	Sep. 30, 2014
Other Income and Expenses [Abstract]	'
Other (Income) Expense, Net	'
	Other (income) expense, net, consisted of:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Interest income	$	(69	)	$	(67	)	$	(190	)	$	(189	)
	Interest expense	191			215			567			600
	Exchange losses	61			11			114			278
	Other, net	(325		)	13			(1,228		)	(33		)
		$	(142	)	$	172		$	(737	)	$	656

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Calculations of Earnings Per Share	'
	The calculations of earnings per share are as follows:
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
	($ and shares in millions except per share amounts)	2014		2013		2014		2013
	Net income attributable to Merck & Co., Inc.	$	895	$	1,124	$	4,604	$	3,623
	Average common shares outstanding	2,879		2,927		2,909		2,975
	Common shares issuable (1)	32		33		33		32
	Average common shares outstanding assuming dilution	2,911		2,960		2,942		3,007
	Basic earnings per common share attributable to Merck & Co., Inc. common shareholders	$	0.31	$	0.38	$	1.58	$	1.22
	Earnings per common share assuming dilution attributable to Merck & Co., Inc. common shareholders	$	0.31	$	0.38	$	1.57	$	1.2
	(1)	Issuable primarily under share-based compensation plans.

Other_Comprehensive_Income_Los1

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Changes in AOCI by Component	'
	Changes in AOCI by component are as follows:
		Three Months Ended September 30,
	($ in millions)	Derivatives				Investments				Employee				Cumulative			Accumulated Other
										Benefit				Translation			Comprehensive
										Plans				Adjustment			Income (Loss)
	Balance July 1, 2013, net of taxes	$	174			$	(7	)		$	(3,455	)		$	(1,472	)	$	(4,760	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	(165		)		55				(7		)		74			(43		)
	Tax	63				(8		)		—				(2		)	53
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	(102		)		47				(7		)		72			10
	Reclassification adjustments, pretax	—				(9		)		73				—			64
	Tax	—				5				(17		)		—			(12		)
	Reclassification adjustments, net of taxes	—			(1)	(4		)	(2)	56			(3)	—			52
	Other comprehensive income (loss), net of taxes	(102		)		43				49				72			62
	Balance September 30, 2013, net of taxes	$	72			$	36			$	(3,406	)		$	(1,400	)	$	(4,698	)
	Balance July 1, 2014, net of taxes	$	27			$	116			$	(1,241	)		$	(1,346	)	$	(2,444	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	434				(26		)		(715		)		(244		)	(551		)
	Tax	(152		)		(7		)		226				(72		)	(5		)
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	282				(33		)		(489		)		(316		)	(556		)
	Reclassification adjustments, pretax	(44		)		5				34				—			(5		)
	Tax	16				(1		)		(8		)		—			7
	Reclassification adjustments, net of taxes	(28		)	(1)	4			(2)	26			(3)	—			2
	Other comprehensive income (loss), net of taxes	254				(29		)		(463		)		(316		)	(554		)
	Balance September 30, 2014, net of taxes	$	281			$	87			$	(1,704	)		$	(1,662	)	$	(2,998	)
		Nine Months Ended September 30,
	($ in millions)	Derivatives				Investments				Employee				Cumulative			Accumulated Other
										Benefit				Translation			Comprehensive
										Plans				Adjustment			Income (Loss)
	Balance January 1, 2013, net of taxes	$	(97	)		$	73			$	(3,667	)		$	(991	)	$	(4,682	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	248				11				137				(304		)	92
	Tax	(100		)		(16		)		(30		)		(105		)	(251		)
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	148				(5		)		107				(409		)	(159		)
	Reclassification adjustments, pretax	33				(43		)		215				—			205
	Tax	(12		)		11				(61		)		—			(62		)
	Reclassification adjustments, net of taxes	21			(1)	(32		)	(2)	154			(3)	—			143
	Other comprehensive income (loss), net of taxes	169				(37		)		261				(409		)	(16		)
	Balance September 30, 2013, net of taxes	$	72			$	36			$	(3,406	)		$	(1,400	)	$	(4,698	)
	Balance January 1, 2014, net of taxes	$	132			$	54			$	(909	)		$	(1,474	)	$	(2,197	)
	Other comprehensive income (loss) before reclassification adjustments, pretax	277				13				(1,287		)		(123		)	(1,120		)
	Tax	(97		)		(2		)		449				(65		)	285
	Other comprehensive income (loss) before reclassification adjustments, net of taxes	180				11				(838		)		(188		)	(835		)
	Reclassification adjustments, pretax	(48		)		35				54				—			41
	Tax	17				(13		)		(11		)		—			(7		)
	Reclassification adjustments, net of taxes	(31		)	(1)	22			(2)	43			(3)	—			34
	Other comprehensive income (loss), net of taxes	149				33				(795		)		(188		)	(801		)
	Balance September 30, 2014, net of taxes	$	281			$	87			$	(1,704	)		$	(1,662	)	$	(2,998	)
	(1) Relates to foreign currency cash flow hedges that were reclassified from AOCI to Sales.
	(2) Represents net realized (gains) losses on the sales of available-for-sale investments that were reclassified from AOCI to Other (income) expense, net.
	(3) Includes net amortization of prior service cost and actuarial gains and losses included in net periodic benefit cost (see Note 12).

Segment_Reporting_Tables

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Sales of Company's Products	'
	Sales of the Company’s products were as follows:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Primary Care and Women’s Health
	Cardiovascular
	Zetia	$	660		$	662		$	1,988		$	1,941
	Vytorin	369			396			1,146			1,207
	Diabetes
	Januvia/Janumet	1,439			1,369			4,350			4,208
	General Medicine and Women’s Health
	NuvaRing	186			170			531			492
	Implanon/Nexplanon	158			96			379			282
	Dulera	124			82			328			229
	Follistim AQ	97			124			309			380
	Hospital and Specialty
	Hepatitis
	PegIntron	84			104			300			372
	Victrelis	27			121			132			347
	HIV
	Isentress	412			427			1,255			1,201
	Acute Care
	Cancidas	183			151			505			477
	Invanz	141			130			390			360
	Noxafil	107			75			280			212
	Bridion	90			75			245			206
	Primaxin	91			88			243			256
	Immunology
	Remicade	604			574			1,815			1,651
	Simponi	170			126			500			354
	Other
	Cosopt/Trusopt	34			104			232			313
	Oncology
	Emend	136			123			402			373
	Temodar	88			162			264			596
	Diversified Brands
	Respiratory
	Nasonex	261			297			830			1,008
	Singulair	218			280			773			898
	Clarinex	49			54			180			180
	Other
	Cozaar/Hyzaar	195			238			614			760
	Arcoxia	132			112			400			354
	Fosamax	114			140			358			421
	Propecia	66			71			197			206
	Zocor	61			65			194			221
	Remeron	47			44			137			150
	Vaccines (1)
	Gardasil	590			665			1,382			1,438
	ProQuad/M-M-R II/Varivax	421			421			1,027			1,032
	RotaTeq	174			201			490			507
	Zostavax	181			185			479			494
	Pneumovax 23	197			193			400			412
	Other pharmaceutical (2)	1,228			1,350			3,617			4,139
	Total Pharmaceutical segment sales	9,134			9,475			26,672			27,677
	Other segment sales (3)	1,321			1,501			4,657			4,844
	Total segment sales	10,455			10,976			31,329			32,521
	Other (4)	102			56			426			192
		$	10,557		$	11,032		$	31,755		$	32,713
	(1)	These amounts do not reflect sales of vaccines sold in most major European markets through the Company’s joint venture, Sanofi Pasteur MSD, the results of which are reflected in Equity income from affiliates. These amounts do, however, reflect supply sales to Sanofi Pasteur MSD.
	(2)	Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately.
	(3)	Represents the non-reportable segments of Animal Health, Consumer Care and Alliances. The Alliances segment includes revenue from the Company’s relationship with AZLP until its termination on June 30, 2014 (see Note 7). On October 1, 2014, the Company sold its Consumer Care business to Bayer (see Note 3).
	(4)	Other revenues are primarily comprised of miscellaneous corporate revenues, sales related to divested products or businesses, and other supply sales not included in segment results. Other revenues in the first nine months of 2014 include $232 million received by Merck in connection with the sale of the U.S. marketing rights to Saphris (see Note 3). Other revenues also include third-party manufacturing sales, a substantial portion of which was divested in October 2013 (see Note 2).
Reconciliation of Segment Profits to Income Before Taxes	'
	A reconciliation of segment profits to Income before taxes is as follows:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
	($ in millions)	2014			2013			2014			2013
	Segment profits:
	Pharmaceutical segment	$	5,772		$	5,983		$	16,475		$	17,022
	Other segments	539			750			2,050			2,445
	Total segment profits	6,311			6,733			18,525			19,467
	Other profits (losses)	79			(6		)	370			(24		)
	Unallocated:
	Interest income	69			67			190			189
	Interest expense	(191		)	(215		)	(567		)	(600		)
	Equity income from affiliates	(22		)	(67		)	62			(82		)
	Depreciation and amortization	(595		)	(512		)	(1,895		)	(1,449		)
	Research and development	(1,332		)	(1,419		)	(3,984		)	(4,928		)
	Amortization of purchase accounting adjustments	(1,008		)	(1,176		)	(3,198		)	(3,545		)
	Restructuring costs	(376		)	(870		)	(664		)	(1,144		)
	AstraZeneca option exercise	—			—			741			—
	Gain on divestiture of certain ophthalmic products	396			—			396			—
	Other unallocated, net	(1,841		)	(1,010		)	(4,504		)	(3,564		)
		$	1,490		$	1,525		$	5,472		$	4,320

Restructuring_Textual_Detail

Restructuring - Textual (Detail) (USD $)

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Oct. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Jan. 31, 2014

Dec. 31, 2013

Dec. 31, 2013

2013 Restructuring Program [Member]

2013 Restructuring Program [Member]

2013 Restructuring Program [Member]

2013 Restructuring Program [Member]

2013 Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

2008 Restructuring Program [Member]

2008 Restructuring Program [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

API manufacturing business [Member]

API manufacturing business [Member]

API manufacturing business [Member]

position

position

position

position

position

position

position

position

2013 Restructuring Program [Member]

Merger Restructuring Program [Member]

2013 Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

Merger Restructuring Program [Member]

Restructuring Cost and Reserve [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total number of positions expected to be eliminated

'

'

'

'

8,500

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total pretax restructuring costs

$612,000,000

$967,000,000

$1,359,000,000

$1,439,000,000

'

$437,000,000

$544,000,000

$826,000,000

$544,000,000

$175,000,000

$423,000,000

$533,000,000

$841,000,000

$0

$54,000,000

'

'

'

'

'

'

'

Cumulative restructuring costs incurred to date since program inception

'

'

'

'

'

2,100,000,000

'

2,100,000,000

'

7,700,000,000

'

7,700,000,000

'

'

'

'

'

'

'

'

'

'

Positions eliminated since inception of program

'

'

'

'

'

4,965

'

4,965

'

27,855

'

27,855

'

'

'

'

'

'

'

'

'

'

Expected cumulative restructuring costs, pretax

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,500,000,000

7,900,000,000

3,000,000,000

8,200,000,000

'

'

'

Proceeds from divestiture of businesses

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

533,000,000

172,000,000

705,000,000

Noncash or part noncash divestiture, amount of consideration received

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$198,000,000

'

Remaining positions expected to be eliminated

'

'

'

'

'

'

'

'

'

4,445

'

4,445

'

'

'

'

'

'

'

'

'

'

Percentage estimate of cumulative pretax costs that will result in cash outlays (primarily from employee separation expense)

'

'

'

'

'

'

'

66.67%

'

'

'

66.67%

'

'

'

'

'

'

'

'

'

'

Percentage estimate of cumulative pretax costs that will be non-cash (primarily from accelerated depreciation of facilities)

'

'

'

'

'

'

'

33.33%

'

'

'

33.33%

'

'

'

'

'

'

'

'

'

'

Number of positions eliminated

'

'

'

'

'

830

'

3,425

'

185

1,070

975

2,475

'

55

'

'

'

'

'

'

'

Restructuring_Charges_Related_

Restructuring - Charges Related to Restructuring Program Activities by Type of Cost (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	$4,223	$4,104	$13,019	$12,347
Marketing and administrative	2,975	2,803	8,681	8,929
Research and development	1,659	1,660	4,897	5,668
Restructuring costs	376	870	664	1,144
Total pretax restructuring costs	612	967	1,359	1,439
2013 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	5	20	206	20
Marketing and administrative	45	15	92	15
Research and development	81	8	174	8
Restructuring costs	306	501	354	501
Total pretax restructuring costs	437	544	826	544
Merger Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	82	37	171	169
Marketing and administrative	23	16	51	45
Research and development	0	1	1	30
Restructuring costs	70	369	310	597
Total pretax restructuring costs	175	423	533	841
2008 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	0	'	4
Marketing and administrative	'	0	'	4
Restructuring costs	'	0	'	46
Total pretax restructuring costs	'	0	'	54
Separation Costs [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Total pretax restructuring costs	315	742	491	970
Separation Costs [Member] | 2013 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	'	'	'
Marketing and administrative	'	'	'	'
Research and development	'	'	'	'
Restructuring costs	310	501	387	501
Total pretax restructuring costs	310	501	387	501
Separation Costs [Member] | Merger Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	'	'	'
Marketing and administrative	'	'	'	'
Research and development	'	'	'	'
Restructuring costs	5	241	104	435
Total pretax restructuring costs	5	241	104	435
Separation Costs [Member] | 2008 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	'	'	'
Marketing and administrative	'	'	'	'
Restructuring costs	'	0	'	34
Total pretax restructuring costs	'	0	'	34
Accelerated Depreciation [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Total pretax restructuring costs	221	94	714	210
Accelerated Depreciation [Member] | 2013 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	5	20	189	20
Marketing and administrative	45	15	92	15
Research and development	75	8	160	8
Restructuring costs	'	'	'	'
Total pretax restructuring costs	125	43	441	43
Accelerated Depreciation [Member] | Merger Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	67	30	219	91
Marketing and administrative	29	20	54	44
Research and development	0	1	0	30
Restructuring costs	'	'	'	'
Total pretax restructuring costs	96	51	273	165
Accelerated Depreciation [Member] | 2008 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	0	'	-2
Marketing and administrative	'	0	'	4
Restructuring costs	'	'	'	'
Total pretax restructuring costs	'	0	'	2
Other [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Total pretax restructuring costs	76	131	154	259
Other [Member] | 2013 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	0	0	17	0
Marketing and administrative	0	0	0	0
Research and development	6	0	14	0
Restructuring costs	-4	0	-33	0
Total pretax restructuring costs	2	0	-2	0
Other [Member] | Merger Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	15	7	-48	78
Marketing and administrative	-6	-4	-3	1
Research and development	0	0	1	0
Restructuring costs	65	128	206	162
Total pretax restructuring costs	74	131	156	241
Other [Member] | 2008 Restructuring Program [Member]	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'
Materials and production	'	0	'	6
Marketing and administrative	'	0	'	0
Restructuring costs	'	0	'	12
Total pretax restructuring costs	'	$0	'	$18

Restructuring_Charges_and_Spen

Restructuring - Charges and Spending Relating to Restructuring Activities by Program (Detail) (USD $)	3 Months Ended			9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
Restructuring Reserve [Roll Forward]	'		'	'		'
Expense	$612		$967	$1,359		$1,439
2013 Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	768		'
Expense	437		544	826		544
(Payments) receipts, net	'		'	-642		'
Non-cash activity	'		'	-398		'
Restructuring reserve, ending balance	554	[1]	'	554	[1]	'
Merger Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	737		'
Expense	175		423	533		841
(Payments) receipts, net	'		'	-408		'
Non-cash activity	'		'	-263		'
Restructuring reserve, ending balance	599	[1]	'	599	[1]	'
Separation Costs [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Expense	315		742	491		970
Separation Costs [Member] | 2013 Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	745		'
Expense	310		501	387		501
(Payments) receipts, net	'		'	-596		'
Non-cash activity	'		'	0		'
Restructuring reserve, ending balance	536	[1]	'	536	[1]	'
Separation Costs [Member] | Merger Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	725		'
Expense	5		241	104		435
(Payments) receipts, net	'		'	-237		'
Non-cash activity	'		'	0		'
Restructuring reserve, ending balance	592	[1]	'	592	[1]	'
Accelerated Depreciation [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Expense	221		94	714		210
Accelerated Depreciation [Member] | 2013 Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	0		'
Expense	125		43	441		43
(Payments) receipts, net	'		'	0		'
Non-cash activity	'		'	-441		'
Restructuring reserve, ending balance	0	[1]	'	0	[1]	'
Accelerated Depreciation [Member] | Merger Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	0		'
Expense	96		51	273		165
(Payments) receipts, net	'		'	0		'
Non-cash activity	'		'	-273		'
Restructuring reserve, ending balance	0	[1]	'	0	[1]	'
Other [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Expense	76		131	154		259
Other [Member] | 2013 Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	23		'
Expense	2		0	-2		0
(Payments) receipts, net	'		'	-46		'
Non-cash activity	'		'	43		'
Restructuring reserve, ending balance	18	[1]	'	18	[1]	'
Other [Member] | Merger Restructuring Program [Member]	'		'	'		'
Restructuring Reserve [Roll Forward]	'		'	'		'
Restructuring reserve, beginning balance	'		'	12		'
Expense	74		131	156		241
(Payments) receipts, net	'		'	-171		'
Non-cash activity	'		'	10		'
Restructuring reserve, ending balance	$7	[1]	'	$7	[1]	'
[1]	The cash outlays associated with the 2013 Restructuring Program are expected to be substantially completed by the end of 2015. The non-manufacturing cash outlays associated with the Merger Restructuring Program were substantially completed by the end of 2013; the remaining cash outlays are expected to be substantially completed by 2016.

Acquisitions_Divestitures_Rese2

Acquisitions, Divestitures, Research Collaborations and License Agreements - Textual (Detail) (USD $)

3 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

9 Months Ended

3 Months Ended

3 Months Ended

0 Months Ended

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Jul. 01, 2014

Sep. 30, 2014

31-May-14

31-May-14

Aug. 31, 2014

Mar. 31, 2014

Jun. 30, 2014

Mar. 31, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Apr. 30, 2013

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

Feb. 28, 2013

Dec. 31, 2014

Oct. 01, 2014

Oct. 01, 2014

Oct. 01, 2014

Santen Pharmaceutical Co. Ltd. [Member]

Santen Pharmaceutical Co. Ltd. [Member]

Santen Pharmaceutical Co. Ltd. [Member]

Santen Pharmaceutical Co. Ltd. [Member]

Idenix Pharmaceuticals, Inc. [Member]

Sirna Therapeutics Inc. [Member]

Sirna Therapeutics Inc. [Member]

Sirna Therapeutics Inc. [Member]

Sirna Therapeutics Inc. [Member]

Saphris/Sycrest [Member]

Merck [Member]

Pfizer [Member]

Pfizer [Member]

Pfizer [Member]

Supera [Member]

Supera [Member]

Supera [Member]

Scenario, Forecast [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Minimum [Member]

Maximum [Member]

Santen Pharmaceutical Co. Ltd. [Member]

Santen Pharmaceutical Co. Ltd. [Member]

Bayer AG [Member]

Consumer Care [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Consideration Transferred

'

'

'

'

'

'

'

'

'

$3,900,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition, Purchase Price Allocation, In-process research and development

'

'

'

'

'

'

'

'

'

3,200,000,000

'

'

'

'

'

'

'

'

'

'

'

100,000,000

'

'

'

'

Business Acquisition, Purchase Price Allocation, Deferred tax liabilities

'

'

'

'

'

'

'

'

'

1,200,000,000

'

'

'

'

'

'

'

'

'

'

'

64,000,000

'

'

'

'

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets

'

'

'

'

'

'

'

'

'

350,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Goodwill

13,171,000,000

'

13,171,000,000

'

12,301,000,000

'

'

'

'

1,500,000,000

'

'

'

'

'

'

'

'

'

'

'

103,000,000

'

'

'

'

Fair Value Inputs, Discount Rate

'

'

'

'

'

'

'

'

'

11.50%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Disposition of Business Agreement Term

'

'

'

'

'

'

'

'2 years

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from divestiture of businesses

'

'

'

'

'

515,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50,000,000

'

14,200,000,000

Gain (Loss) on Disposition of Business

'

'

396,000,000

0

'

'

396,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100,000,000

'

'

'

Proceeds from sale of technology assets

'

'

'

'

'

'

'

'

'

'

25,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares received in consideration for sale of technology assets

'

'

'

'

'

'

'

'

'

'

2,520,044

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of shares received from sale of technology assets

'

'

'

'

'

'

'

'

'

'

'

15.00%

85.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

Value of shares received to date from sale of technology assets

'

'

'

'

'

'

'

'

'

'

'

22,000,000

172,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Gain on disposition of technology assets

'

'

168,000,000

'

'

'

'

'

'

'

'

'

'

204,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Taxes on Income

648,000,000

375,000,000

865,000,000

618,000,000

'

'

'

'

'

'

'

'

'

-300,000,000

'

'

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Other than Temporary Impairment

'

'

'

'

'

'

'

'

'

'

'

36,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from sale of intangible assets

'

'

'

'

'

'

'

'

'

'

'

'

'

'

232,000,000

'

'

'

'

'

'

'

'

'

'

'

Upfront and milestone payments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60,000,000

'

'

'

'

'

'

1,000,000,000

'

Percentage share of potential revenues and certain costs

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

60.00%

'

'

40.00%

'

'

'

'

'

'

'

Length of time to give notice to terminate the agreement

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'12 months

'

'

'

'

'

'

'

'

'

Controlling interest of ownership in joint venture

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

51.00%

'

'

'

'

Non-controlling interest of ownership in joint venture

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

49.00%

'

'

'

'

Business Acquisition, Purchase Price Allocation, Currently marketed products

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

89,000,000

'

'

'

'

Business Acquisition, Purchase Price Allocation, Increases to Noncontrolling interests

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

112,000,000

'

'

'

'

Business Combination Acquisition of Less than 100 Percent Controlling Interest Fair Value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

116,000,000

'

'

'

'

Intangible asset impairment charges related to IPR&D

36,000,000

'

'

264,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

31,000,000

15,000,000

'

'

'

'

'

Goodwill, Impairment Loss

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$93,000,000

'

'

'

'

'

'

Extended period of marketing rights

'

'

'15 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Acquisitions_Divestitures_Rese3

Acquisitions, Divestitures, Research Collaborations and License Agreements - Merck Consumer Care (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Oct. 01, 2014	Oct. 01, 2014	Oct. 01, 2014
			Consumer Care [Member]	Scenario, Forecast [Member]	Subsequent Event [Member]	Subsequent Event [Member]
				Consumer Care [Member]	Consumer Care [Member]	Bayer AG [Member]
Business Acquisition [Line Items]	'	'	'	'	'	'
Proceeds from divestiture of businesses	'	'	'	'	$14,200,000,000	'
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal	'	'	'	11,000,000,000	'	'
Upfront and milestone payments	'	'	'	'	'	1,000,000,000
Assets of Disposal Group, Including Discontinued Operation [Abstract]	'	'	'	'	'	'
Accounts receivable, net	'	'	79,000,000	'	'	'
Inventories	'	'	278,000,000	'	'	'
Deferred income taxes and other current assets	'	'	25,000,000	'	'	'
Property, plant and equipment, net	'	'	212,000,000	'	'	'
Goodwill	'	'	162,000,000	'	'	'
Other intangibles, net	'	'	2,194,000,000	'	'	'
Other assets	'	'	56,000,000	'	'	'
Assets of Disposal Group, Including Discontinued Operation, Current	3,302,000,000	26,000,000	3,006,000,000	'	'	'
Liabilities of Disposal Group, Including Discontinued Operation [Abstract]	'	'	'	'	'	'
Trade accounts payable	'	'	84,000,000	'	'	'
Accrued and other current liabilities	'	'	114,000,000	'	'	'
Deferred income taxes	'	'	561,000,000	'	'	'
Other noncurrent liabilities	'	'	6,000,000	'	'	'
Liabilities of Disposal Group, Including Discontinued Operation, Current	$810,000,000	$0	$765,000,000	'	'	'

Financial_Instruments_Textual_

Financial Instruments - Textual (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012
	Interest_Rate_Swap
Derivative [Line Items]	'	'	'	'
Derivative, Net Hedge Ineffectiveness Gain (Loss)	$3,000,000	'	'	'
Maximum planning cycle of third-party sales hedges	'3 years	'	'	'
Maximum average period of maturities of contracts in years	'1 year	'	'	'
Pretax gains (losses) from euro-denominated notes included in cumulative translation adjustments	166,000,000	-33,000,000	'	'
Interest rate swaps outstanding	11	'	'	'
Derivative, Notional Amount	30,408,000,000	'	29,909,000,000	'
Pretax net unrealized gains on derivatives maturing within next 12 months estimated to be reclassified from AOCI to sales	256,000,000	'	'	'
Available-for-sale debt securities included in Short-term investments	3,000,000,000	'	'	'
Available-for-sale debt securities maturing after one year through five years	12,100,000,000	'	'	'
Cash and cash equivalents	11,370,000,000	14,090,000,000	15,621,000,000	13,451,000,000
Cash equivalents	10,400,000,000	'	'	'
Fair value of loans payable and long-term debt, including current portion	29,000,000,000	'	25,500,000,000	'
Carrying value of loans payable and long-term debt, including current portion	27,800,000,000	'	25,100,000,000	'
Accounts receivable classified in Other assets	275,000,000	'	275,000,000	'
Accounts receivable outstanding for more than one year	165,000,000	'	'	'
Cash collateral received from counterparties	942,000,000	'	652,000,000	'
Derivative, Cash Received on Hedge	3,000,000	'	'	'
Greece, Italy, Spain and Portugal [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Accounts receivable in Greece, Italy, Spain and Portugal	900,000,000	'	'	'
Percentage of total accounts receivable outstanding for more than one year that relates to Greece, Italy, Spain and Portugal	45.00%	'	'	'
Greece, Italy, Spain and Portugal [Member] | Hospital and public sector [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Accounts receivable in Greece, Italy, Spain and Portugal	590,000,000	'	'	'
Greece [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Percentage of total hospital and public sector accounts receivable in Greece, Italy, Spain and Portugal in the aggregate that relate to specified country	12.00%	'	'	'
Italy [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Percentage of total hospital and public sector accounts receivable in Greece, Italy, Spain and Portugal in the aggregate that relate to specified country	37.00%	'	'	'
Spain [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Percentage of total hospital and public sector accounts receivable in Greece, Italy, Spain and Portugal in the aggregate that relate to specified country	41.00%	'	'	'
Portugal [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Percentage of total hospital and public sector accounts receivable in Greece, Italy, Spain and Portugal in the aggregate that relate to specified country	13.00%	'	'	'
5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest rate swaps outstanding	3	'	'	'
0.70% Notes Due 2016 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest rate swaps outstanding	4	'	'	'
1.30% Notes Due 2018 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest rate swaps outstanding	4	'	'	'
0.70% Notes Due 2016 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	0.70%	'	'	'
1.30% Notes Due 2018 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	1.30%	'	'	'
6.00% Notes Due 2017 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	6.00%	'	'	'
5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	5.00%	'	'	'
$150 Million Notional Amount [Member] | 5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest rate swaps outstanding	1	'	'	'
Interest Rate Swap [Member] | 0.70% Notes Due 2016 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Derivative, Notional Amount	250,000,000	'	'	'
Interest Rate Swap [Member] | 1.30% Notes Due 2018 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Derivative, Notional Amount	250,000,000	'	'	'
Interest Rate Swap [Member] | $150 Million Notional Amount [Member] | 5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Derivative, Notional Amount	150,000,000	'	'	'
Interest Rate Swap [Member] | $200 Million Notional Amounts [Member] | 5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Derivative, Notional Amount	200,000,000	'	'	'
$200 Million Notional Amounts [Member] | 5.00% Notes Due 2019 [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest rate swaps outstanding	2	'	'	'
Significant Unobservable Inputs (Level 3) [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Business Combination, Contingent Consideration, Liability	$75,000,000	'	$69,000,000	'

Financial_Instruments_Fair_Val

Financial Instruments - Fair Value of Derivatives Segregated between those Derivatives that are Designated as Hedging Instruments and those that are Not Designated as Hedging Instruments (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	$1,360,000,000	$1,090,000,000
Fair Value of Derivative, Liability	94,000,000	184,000,000
U.S. Dollar Notional	30,408,000,000	29,909,000,000
Derivatives Designated as Hedging Instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	1,126,000,000	1,021,000,000
Fair Value of Derivative, Liability	24,000,000	44,000,000
U.S. Dollar Notional	16,529,000,000	16,312,000,000
Derivatives Not Designated as Hedging Instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	234,000,000	69,000,000
Fair Value of Derivative, Liability	70,000,000	140,000,000
U.S. Dollar Notional	13,879,000,000	13,597,000,000
Interest Rate Swap [Member] | Derivatives Designated as Hedging Instruments [Member] | Other assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	8,000,000	13,000,000
Fair Value of Derivative, Liability	'	'
U.S. Dollar Notional	550,000,000	1,550,000,000
Interest Rate Swap [Member] | Derivatives Designated as Hedging Instruments [Member] | Other Noncurrent Liabilities [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	'	'
Fair Value of Derivative, Liability	22,000,000	25,000,000
U.S. Dollar Notional	2,000,000,000	2,000,000,000
Foreign Exchange Contracts [Member] | Derivatives Designated as Hedging Instruments [Member] | Other assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	491,000,000	515,000,000
Fair Value of Derivative, Liability	'	'
U.S. Dollar Notional	6,238,000,000	6,676,000,000
Foreign Exchange Contracts [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	627,000,000	493,000,000
Fair Value of Derivative, Liability	'	'
U.S. Dollar Notional	7,157,000,000	4,427,000,000
Foreign Exchange Contracts [Member] | Derivatives Designated as Hedging Instruments [Member] | Accrued and other current liabilities [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	'	'
Fair Value of Derivative, Liability	1,000,000	19,000,000
U.S. Dollar Notional	464,000,000	1,659,000,000
Foreign Exchange Contracts [Member] | Derivatives Designated as Hedging Instruments [Member] | Other Noncurrent Liabilities [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	'	'
Fair Value of Derivative, Liability	1,000,000	0
U.S. Dollar Notional	120,000,000	0
Foreign Exchange Contracts [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	234,000,000	69,000,000
Fair Value of Derivative, Liability	'	'
U.S. Dollar Notional	9,192,000,000	5,705,000,000
Foreign Exchange Contracts [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Accrued and other current liabilities [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair Value of Derivative, Asset	'	'
Fair Value of Derivative, Liability	70,000,000	140,000,000
U.S. Dollar Notional	$4,687,000,000	$7,892,000,000

Financial_Instruments_Informat

Financial Instruments - Information on Derivative Positions Subject to Master Netting Arrangements as if they were Presented on a Net Basis (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'	'
Gross amounts recognized in the consolidated balance sheet, Asset	$1,360	$1,090
Derivative Asset, Fair Value, Gross Liability	-91	-147
Cash collateral (received) posted, Asset	-942	-652
Gross amount subject to offset in master netting arrangements not offset in the consolidated balance sheet, Asset	327	291
Gross amounts recognized in the consolidated balance sheet, Liability	94	184
Derivative Liability, Fair Value, Gross Asset	-91	-147
Cash collateral (received) posted, Liability	'	'
Gross amount subject to offset in master netting arrangements not offset in the consolidated balance sheet, Liability	$3	$37

Financial_Instruments_Location

Financial Instruments - Location and Pretax Gain or Loss Amounts for Derivatives (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Derivatives not designated in a hedging relationship [Member] | Foreign Exchange Contracts [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of (gain) loss recognized in Other (income) expense, net on derivatives	($290)	[1]	$154	[1]	($314)	[1]	$146	[1]
Amount of loss recognized in Sales	5		8		5		5
Derivatives designated in a fair value hedging relationships [Member] | Interest Rate Swap [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of (gain) loss recognized in Other (income) expense, net on derivatives	23	[2]	-33	[2]	2	[2]	1	[2]
Amount of (gain) loss recognized in Other (income) expense, net on hedged items	-23		30		-3		-2
Derivatives designated in foreign currency cash flow hedging relationships [Member] | Foreign Exchange Contracts [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of (gain) loss reclassified from AOCI to Sales	-42		1		-45		36
Amount of loss (gain) recognized in OCI on derivatives	-433		165		-276		-219
Derivatives designated in foreign currency net investment hedging relationships [Member] | Foreign Exchange Contracts [Member]	'		'		'		'
Derivative Instruments, Gain (Loss) [Line Items]	'		'		'		'
Amount of loss (gain) recognized in OCI on derivatives	-116		-15		-67		-259
Amount of gain recognized in Other (income) expense, net on derivatives	($1)	[3]	($5)	[3]	($3)	[3]	($7)	[3]
[1]	These derivative contracts mitigate changes in the value of remeasured foreign currency denominated monetary assets and liabilities attributable to changes in foreign currency exchange rates.
[2]	There was $3 million of ineffectiveness on the hedge during the third quarter and first nine months of 2013.
[3]	There was no ineffectiveness on the hedge. Represents the amount excluded from hedge effectiveness testing.

Financial_Instruments_Informat1

Financial Instruments - Information on Available-for-sale Investments (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	$16,729	$11,868
Amortized Cost	16,600	11,787
Gross Unrealized Gains	151	110
Gross Unrealized Losses	-22	-29
Commercial paper [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	2,121	1,206
Amortized Cost	2,121	1,206
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Corporate notes and bonds [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	9,428	7,054
Amortized Cost	9,411	7,037
Gross Unrealized Gains	31	32
Gross Unrealized Losses	-14	-15
U.S. government and agency securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	2,039	1,236
Amortized Cost	2,042	1,239
Gross Unrealized Gains	0	1
Gross Unrealized Losses	-3	-4
Asset-backed securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	1,440	1,300
Amortized Cost	1,441	1,303
Gross Unrealized Gains	1	1
Gross Unrealized Losses	-2	-4
Mortgage-backed securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	538	476
Amortized Cost	540	479
Gross Unrealized Gains	1	2
Gross Unrealized Losses	-3	-5
Foreign government bonds [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	456	125
Amortized Cost	456	126
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	-1
Equity securities [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Fair Value	707	471
Amortized Cost	589	397
Gross Unrealized Gains	118	74
Gross Unrealized Losses	$0	$0

Financial_Instruments_Financia

Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Assets	'		'
Fair Value	$16,729		$11,868
Derivative assets	1,360		1,090
Liabilities	'		'
Derivative liabilities	94		184
Commercial paper [Member]	'		'
Assets	'		'
Fair Value	2,121		1,206
Corporate notes and bonds [Member]	'		'
Assets	'		'
Fair Value	9,428		7,054
U.S. government and agency securities [Member]	'		'
Assets	'		'
Fair Value	2,039		1,236
Asset-backed securities [Member]	'		'
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis [Line Items]	'		'
Investments, Primary Weighted Average Life of Collateral	'5 years		'
Assets	'		'
Fair Value	1,440		1,300
Foreign government bonds [Member]	'		'
Assets	'		'
Fair Value	456		125
Mortgage-backed securities [Member]	'		'
Assets	'		'
Fair Value	538		476
Equity securities [Member]	'		'
Assets	'		'
Fair Value	707		471
Fair Value, Measurements, Recurring [Member]	'		'
Assets	'		'
Investments	16,469		11,635
Securities held for employee compensation	260		233
Purchased currency options	918	[1]	868	[1]
Derivative assets	1,360	[2]	1,090	[2]
Total assets	18,089		12,958
Liabilities	'		'
Total liabilities	94		184
Fair Value, Measurements, Recurring [Member] | Foreign Exchange Contracts [Member]	'		'
Assets	'		'
Derivative assets	434	[1]	209	[1]
Liabilities	'		'
Derivative liabilities	29	[1]	134	[1]
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member]	'		'
Assets	'		'
Derivative assets	8	[1]	13	[1]
Liabilities	'		'
Derivative liabilities	22	[1]	25	[1]
Fair Value, Measurements, Recurring [Member] | Written currency options [Member]	'		'
Liabilities	'		'
Derivative liabilities	43	[1]	25	[1]
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Investments	447		238
Securities held for employee compensation	198		186
Purchased currency options	'	[1]	'	[1]
Derivative assets	0	[2]	0	[2]
Total assets	645		424
Liabilities	'		'
Total liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member] | Foreign Exchange Contracts [Member]	'		'
Assets	'		'
Derivative assets	'	[1]	'	[1]
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member] | Interest Rate Swap [Member]	'		'
Assets	'		'
Derivative assets	'	[1]	'	[1]
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member] | Written currency options [Member]	'		'
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Investments	16,022		11,397
Securities held for employee compensation	62		47
Purchased currency options	918	[1]	868	[1]
Derivative assets	1,360	[2]	1,090	[2]
Total assets	17,444		12,534
Liabilities	'		'
Total liabilities	94		184
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Foreign Exchange Contracts [Member]	'		'
Assets	'		'
Derivative assets	434	[1]	209	[1]
Liabilities	'		'
Derivative liabilities	29	[1]	134	[1]
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Interest Rate Swap [Member]	'		'
Assets	'		'
Derivative assets	8	[1]	13	[1]
Liabilities	'		'
Derivative liabilities	22	[1]	25	[1]
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Written currency options [Member]	'		'
Liabilities	'		'
Derivative liabilities	43	[1]	25	[1]
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Investments	0		0
Securities held for employee compensation	'		'
Purchased currency options	'	[1]	'	[1]
Derivative assets	0	[2]	0	[2]
Total assets	0		0
Liabilities	'		'
Total liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Foreign Exchange Contracts [Member]	'		'
Assets	'		'
Derivative assets	'	[1]	'	[1]
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Interest Rate Swap [Member]	'		'
Assets	'		'
Derivative assets	'	[1]	'	[1]
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Written currency options [Member]	'		'
Liabilities	'		'
Derivative liabilities	'	[1]	'	[1]
Fair Value, Measurements, Recurring [Member] | Commercial paper [Member]	'		'
Assets	'		'
Fair Value	2,121		1,206
Fair Value, Measurements, Recurring [Member] | Commercial paper [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Commercial paper [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	2,121		1,206
Fair Value, Measurements, Recurring [Member] | Commercial paper [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Corporate notes and bonds [Member]	'		'
Assets	'		'
Fair Value	9,428		7,054
Fair Value, Measurements, Recurring [Member] | Corporate notes and bonds [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Corporate notes and bonds [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	9,428		7,054
Fair Value, Measurements, Recurring [Member] | Corporate notes and bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | U.S. government and agency securities [Member]	'		'
Assets	'		'
Fair Value	2,039		1,236
Fair Value, Measurements, Recurring [Member] | U.S. government and agency securities [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | U.S. government and agency securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	2,039		1,236
Fair Value, Measurements, Recurring [Member] | U.S. government and agency securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member]	'		'
Assets	'		'
Fair Value	1,440	[2]	1,300	[2]
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'	[2]	'	[2]
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	1,440	[2]	1,300	[2]
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'	[2]	'	[2]
Fair Value, Measurements, Recurring [Member] | Foreign government bonds [Member]	'		'
Assets	'		'
Fair Value	456		125
Fair Value, Measurements, Recurring [Member] | Foreign government bonds [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Foreign government bonds [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	456		125
Fair Value, Measurements, Recurring [Member] | Foreign government bonds [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member]	'		'
Assets	'		'
Fair Value	538	[2]	476	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	'	[2]	'	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	538	[2]	476	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'	[2]	'	[2]
Fair Value, Measurements, Recurring [Member] | Equity securities [Member]	'		'
Assets	'		'
Fair Value	447		238
Fair Value, Measurements, Recurring [Member] | Equity securities [Member] | Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]	'		'
Assets	'		'
Fair Value	447		238
Fair Value, Measurements, Recurring [Member] | Equity securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Assets	'		'
Fair Value	'		'
Fair Value, Measurements, Recurring [Member] | Equity securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'		'
Assets	'		'
Fair Value	'		'
[1]	The fair value determination of derivatives includes the impact of the credit risk of counterparties to the derivatives and the Company’s own credit risk, the effects of which were not significant.
[2]	Primarily all of the asset-backed securities are highly-rated (Standard & Poor’s rating of AAA and Moody’s Investors Service rating of Aaa), secured primarily by credit card, auto loan, and home equity receivables, with weighted-average lives of primarily 5 years or less. Mortgage-backed securities represent AAA-rated securities issued or unconditionally guaranteed as to payment of principal and interest by U.S. government agencies.

Inventories_Inventories_Detail

Inventories - Inventories (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Finished goods	$1,811	$1,738
Raw materials and work in process	5,350	5,894
Supplies	212	225
Total (approximates current cost)	7,373	7,857
Increase to LIFO costs	220	73
Total current and noncurrent inventories	7,593	7,930
Recognized as:	'	'
Inventories	5,819	6,226
Other assets	$1,774	$1,704

Inventories_Textual_Detail

Inventories - Textual (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]	'	'
Inventories not expected to be sold within one year included in Other assets	$1,700,000,000	$1,500,000,000
Inventories produced in preparation for product launches included in Other assets	$113,000,000	$177,000,000

Other_Intangibles_Textual_Deta

Other Intangibles - Textual (Detail) (USD $)	3 Months Ended	9 Months Ended		3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2013
				PegIntron [Member]	PegIntron [Member]	Victrelis [Member]	Victrelis [Member]	Rebetol [Member]	Saphris/Sycrest [Member]	Preladenant [Member]
Goodwill And Other Intangible Assets [Line Items]	'	'	'	'	'	'	'	'	'	'
Intangible asset impairment charges related to marketed products	$412	$1,100	'	$270	$523	$107	$137	$35	$330	'
Intangible asset impairment charges related to IPR&D	$36	'	$264	'	'	'	'	'	'	$181

Joint_Ventures_and_Other_Equit2

Joint Ventures and Other Equity Method Affiliates - Equity Income from Affiliates (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Equity Income from Affiliates [Line Items]	'		'		'		'
Equity income from affiliates	$24		$102		$241		$351
Other [Member]	'		'		'		'
Equity Income from Affiliates [Line Items]	'		'		'		'
Equity income from affiliates	24	[1]	30	[1]	49	[1]	49	[1]
AstraZeneca LP [Member]	'		'		'		'
Equity Income from Affiliates [Line Items]	'		'		'		'
Equity income from affiliates	$0	[2]	$72	[2]	$192	[2]	$302	[2]
[1]	Includes results from Sanofi Pasteur MSD.
[2]	As noted below, as of July 1, 2014, the Company no longer records equity income from AZLP.

Joint_Ventures_and_Other_Equit3

Joint Ventures and Other Equity Method Affiliates - Textual (Detail) (USD $)	3 Months Ended	9 Months Ended			12 Months Ended
	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Dec. 31, 1998
				AstraZeneca LP [Member]	AstraZeneca LP [Member]
Equity Income from Affiliates [Line Items]	'	'	'	'	'
Limited partner interest in AZLP	'	'	'	'	1.00%
General partner interest in AZLP	'	'	'	'	99.00%
Proceeds from AstraZeneca option exercise	$0	$419,000,000	'	$419,000,000	'
Portion of exercise price that was deferred	'	'	'	327,000,000	'
Portion of exercise price that represents multiple of average annual profit allocation	'	'	'	91,000,000	'
Multiple of average annual profit allocation to be included in option exercise price	'	'	'	10	'
Years prior to option exercise to be included in average annual profit allocation portion of exercise price	'	'	'	'3 years	'
Non-cash gain recognized upon AstraZeneca option exercise	'	'	'	650,000,000	'
Noncontrolling Interest, Amount Represented by Preferred Stock	'	'	'	'	2,400,000,000
Noncontrolling Interest, Decrease from Redemption or Purchase of Interests	'	2,400,000,000	'	2,400,000,000	'
Reduction in AZLP investment balance related to AstraZeneca option exercise	'	'	'	1,400,000,000	'
Goodwill written off related to AstraZeneca option exercise	'	'	'	340,000,000	'
Deferred income tax expense (benefit) related to AstraZeneca option exercise	'	($1,773,000,000)	($532,000,000)	($517,000,000)	'

Joint_Ventures_and_Other_Equit4

Joint Ventures and Other Equity Method Affiliates - Summarized Financial Information for AZLP (Detail) (AstraZeneca LP [Member], USD $)	3 Months Ended		6 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013		Jun. 30, 2014		Sep. 30, 2013
AstraZeneca LP [Member]	'		'		'
Equity Income from Affiliates [Line Items]	'		'		'
Sales	$1,083		$2,205		$3,383
Materials and production costs	554		1,044		1,681
Other expense, net	398		604		1,198
Income before taxes	$131	[1]	$557	[1]	$504
[1]	Merck’s partnership returns from AZLP were generally contractually determined as noted above and were not based on a percentage of income from AZLP, other than with respect to Merck’s 1% limited partnership interest.

LongTerm_Debt_Details

Long-Term Debt (Details)

1 Months Ended

3 Months Ended

1 Months Ended

Aug. 31, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Oct. 31, 2014

Oct. 01, 2014

USD ($)

USD ($)

USD ($)

6.00% Notes Due 2017 [Member]

Scenario, Forecast [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

Subsequent Event [Member]

USD ($)

USD ($)

1.125% Euro Notes Due 2021 [Member]

1.875% Euro Notes Due 2026 [Member]

2.5% Euro Notes Due 2034 [Member]

4.00% Notes Due 2015 [Member]

6.00% Notes Due 2017 [Member]

5.375% Euro Denominated Notes Due 2014 [Member]

EUR (€)

EUR (€)

EUR (€)

USD ($)

USD ($)

USD ($)

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage

'

'

'

6.00%

'

'

1.13%

1.88%

2.50%

4.00%

6.00%

5.38%

Long-Term Debt

'

$18,566,000,000

$20,539,000,000

'

'

'

€ 1,000,000,000

€ 1,000,000,000

€ 500,000,000

$1,000,000,000

$1,000,000,000

'

Proceeds from Issuance of Debt

'

'

'

'

'

3,100,000,000

'

'

'

'

'

'

Repayments of Debt

'

'

'

'

'

2,500,000,000

'

'

'

'

'

'

Extinguishment of Debt, Amount

'

'

'

'

'

1,800,000,000

'

'

'

'

'

'

Gains (Losses) on Extinguishment of Debt

'

'

'

'

650,000,000

'

'

'

'

'

'

'

Long-term Debt, Current Maturities

'

'

'

'

'

'

'

'

'

'

'

1,900,000,000

Line of Credit Facility, Maximum Borrowing Capacity

$6,000,000,000

'

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Term

'5 years

'

'

'

'

'

'

'

'

'

'

'

Contingencies_Vioxx_Litigation

Contingencies - Vioxx Litigation - Textual (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014
	LegalMatter
Vioxx Cases Brought by State Attorneys General [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	3
Vioxx Securities Lawsuits [Member]	'
Loss Contingencies [Line Items]	'
Upper limits of Directors and Officers insurance coverage	$145,000,000
Vioxx Canadian Litigation [Member] | Minimum [Member]	'
Loss Contingencies [Line Items]	'
Reflects the estimated amount of loss from the specified contingency as of the balance sheet date	21,000,000
Vioxx Canadian Litigation [Member] | Maximum [Member]	'
Loss Contingencies [Line Items]	'
Reflects the estimated amount of loss from the specified contingency as of the balance sheet date	36,000,000
Vioxx [Member] | Cases alleging personal injury [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	50
Vioxx [Member] | Cases alleging economic loss [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	30
Settlement agreement amount	$23,000,000

Contingencies_Fosamax_Product_

Contingencies - Fosamax Product Liability Litigation - Textual (Detail) (Fosamax [Member], USD $)	1 Months Ended	9 Months Ended
	Dec. 31, 2013	Sep. 30, 2014
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	5,555
Number of plaintiffs	'	5,760
Cases Alleging ONJ [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	1,070
ONJ Litigation [Member]	'	'
Loss Contingencies [Line Items]	'	'
Settlement agreement amount	$27,700,000	'
Percentage of participation in litigation settlement condition	100.00%	95.00%
Cases Alleging Femur Fracture [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	4,485
Federal [Member] | ONJ MDL [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	785
Federal [Member] | Femur Fracture MDL [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	1,035
Initial number of cases selected for review	'	33
Loss contingency, claims dismissed number	'	650
New Jersey State Court [Member] | Cases Alleging ONJ [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	275
New Jersey State Court [Member] | Cases Alleging Femur Fracture [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	2,920
Initial number of cases selected for review	'	30
Subsequent number of cases selected for review	'	50
California State Court [Member] | Cases Alleging Femur Fracture [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	520
Initial number of cases selected for review	'	10
Number of additional trials scheduled	'	2
Other State Court [Member] | Cases Alleging Femur Fracture [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, pending claims number	'	5

Contingencies_JanuviaJanumet_L

Contingencies - Januvia/Janumet Litigation - Textual (Detail) (Januvia [Member])	Sep. 30, 2014
	LegalMatter
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	700
Cases Company Agreed ToToll Statute Of Limitations [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	19

Contingencies_NuvaRing_Litigat

Contingencies - NuvaRing Litigation - Textual (Detail) (NuvaRing [Member], USD $)	9 Months Ended
	Sep. 30, 2014
	LegalMatter
Loss Contingencies [Line Items]	'
Percentage of participation in litigation settlement condition	95.00%
Settlement agreement amount	$100,000,000
Loss contingency, pending claims number	1,945
New Jersey State Court [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	215
Other State Court [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	7
NuvaRing MDL [Member] | Federal [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	1,720

Contingencies_PropeciaProscar_

Contingencies - Propecia/Proscar Litigation - Textual (Detail)	9 Months Ended
	Sep. 30, 2014
	plaintiff
	LegalMatter
Propecia [Member]	'
Loss Contingencies [Line Items]	'
Loss contingency, pending claims number	1,245
Number of plaintiffs	1,515
Propecia - Prostate Cancer [Member]	'
Loss Contingencies [Line Items]	'
Number of plaintiffs	45

Contingencies_Legal_Defense_Re

Contingencies - Legal Defense Reserves - Textual (Detail) (Legal Defense Costs [Member], USD $)	Sep. 30, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Legal Defense Costs [Member]	'	'
Loss Contingencies [Line Items]	'	'
Legal defense costs reserve	$180	$160

Equity_Shareholders_Equity_Det

Equity - Shareholders' Equity (Detail) (USD $)

3 Months Ended

9 Months Ended

9 Months Ended

In Millions, except Share data, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Other Paid-In Capital [Member]

Other Paid-In Capital [Member]

Retained Earnings [Member]

Retained Earnings [Member]

Accumulated Other Comprehensive Loss [Member]

Accumulated Other Comprehensive Loss [Member]

Treasury Stock [Member]

Treasury Stock [Member]

Noncontrolling Interest [Member]

Noncontrolling Interest [Member]

Increase (Decrease) in Stockholders' Equity [Roll Forward]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares, Beginning Balance

'

'

3,577,103,522

'

3,577,000,000

3,577,000,000

3,577,000,000

3,577,000,000

'

'

'

'

'

'

650,000,000

550,000,000

'

'

Equity, Beginning Balance

'

'

$52,326

$55,463

$1,788

$1,788

$1,788

$1,788

$40,508

$40,646

$39,257

$39,985

($2,197)

($4,682)

($29,591)

($24,717)

$2,561

$2,443

Net Income Attributable to Merck & Co., Inc.

895

1,124

4,604

3,623

'

'

'

'

'

'

4,604

3,623

'

'

'

'

'

'

Cash dividends declared on common stock

'

'

-3,872

-3,835

'

'

'

'

'

'

-3,872

-3,835

'

'

'

'

'

'

Treasury stock shares purchased, Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

106,000,000

129,000,000

'

'

Treasury stock shares purchased

'

'

-6,083

-6,320

'

'

'

'

'

-500

'

'

'

'

-6,083

-5,820

'

'

Share-based compensation plans and other

'

'

1,657

845

'

'

'

'

-168

-353

'

'

'

'

1,779

1,184

46

14

Share-based compensation plans and other, Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-40,000,000

-29,000,000

'

'

Other comprehensive income (loss)

-554

62

-801

-16

'

'

'

'

'

'

'

'

-801

-16

'

'

'

'

AstraZeneca option exercise

'

'

-2,400

'

'

'

'

'

'

'

'

'

'

'

'

'

-2,400

'

Supera joint venture

'

'

'

228

'

'

'

'

'

116

'

'

'

'

'

'

'

112

Net income attributable to noncontrolling interests

-53

26

3

79

'

'

'

'

'

'

'

'

'

'

'

'

3

79

Distributions attributable to noncontrolling interests

'

'

-74

-61

'

'

'

'

'

'

'

'

'

'

'

'

-74

-61

Shares, Ending balance

3,577,103,522

'

3,577,103,522

'

3,577,000,000

3,577,000,000

3,577,000,000

3,577,000,000

'

'

'

'

'

'

716,000,000

650,000,000

'

'

Equity, Ending Balance

$45,360

$50,006

$45,360

$50,006

$1,788

$1,788

$1,788

$1,788

$40,340

$39,909

$39,989

$39,773

($2,998)

($4,698)

($33,895)

($29,353)

$136

$2,587

Equity_Textual_Detail

Equity - Textual (Detail) (USD $)

9 Months Ended

12 Months Ended

9 Months Ended

0 Months Ended

0 Months Ended

6 Months Ended

Share data in Millions, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 1998

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2013

20-May-13

21-May-13

Oct. 31, 2013

20-May-13

Oct. 31, 2013

Dec. 31, 1998

Treasury Stock [Member]

Treasury Stock [Member]

Other Paid-In Capital [Member]

Accelerated share repurchase agreement (ASR) [Member]

Accelerated share repurchase agreement (ASR) [Member]

Accelerated share repurchase agreement (ASR) [Member]

Accelerated share repurchase agreement (ASR) [Member]

Accelerated share repurchase agreement (ASR) [Member]

AstraZeneca LP [Member]

Treasury Stock [Member]

Treasury Stock [Member]

Treasury Stock [Member]

Purchases of treasury stock

$6,083,000,000

$6,320,000,000

'

'

'

'

$5,000,000,000

'

'

'

'

'

Treasury stock shares purchased, Shares

'

'

'

106

129

'

'

'

5.5

99.5

105

'

Noncontrolling Interest, Amount Represented by Preferred Stock

'

'

'

'

'

'

'

'

'

'

'

2,400,000,000

Payment under Accelerated Share Repurchase agreement

'

'

'

'

'

'

'

4,500,000,000

'

'

'

'

Other paid-in capital

$6,083,000,000

$6,320,000,000

'

$6,083,000,000

$5,820,000,000

$500,000,000

$500,000,000

'

'

'

'

'

Preferred stock assumed with Astra Merck Inc. dividend per annum

'

'

5.00%

'

'

'

'

'

'

'

'

'

ShareBased_Compensation_Plans_1

Share-Based Compensation Plans - Amounts of Share-Based Compensation Cost Recorded in Consolidated Statement of Income (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'	'	'
Pretax share-based compensation expense	$75	$68	$209	$210
Income tax benefit	-23	-21	-64	-64
Total share-based compensation expense, net of taxes	$52	$47	$145	$146

ShareBased_Compensation_Plans_2

Share-Based Compensation Plans - Textual (Detail) (USD $)	9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'
Number of RSUs granted during the period	5	6
Weighted-average grant date fair value of RSUs issued during the period	$58.15	$45.04
Options granted by company	5	6
Weighted- average exercise price of options granted in period	$58.15	$45
Weighted- average fair value per option granted	$6.79	$6.21
Total pretax unrecognized compensation expense related to nonvested stock options, RSU and PSU awards	$502	'
Weighted average period in years of recognition for nonvested stock options, RSU and PSU awards	'1 year 11 months	'

ShareBased_Compensation_Plans_3

Share-Based Compensation Plans - Assumptions Used to Determine Weighted-Average Fair Value of Options Granted (Detail)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'
Expected dividend yield	4.30%	4.20%
Risk-free interest rate	2.00%	1.20%
Expected volatility	22.00%	25.00%
Expected life (years)	'6 years 5 months	'7 years

Pension_and_Other_Postretireme2

Pension and Other Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Pension Plans, Defined Benefit [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	$128	$167	$428	$512
Interest cost	173	166	524	497
Expected return on plan assets	-300	-270	-901	-817
Net amortization	41	86	96	252
Termination benefits	16	5	47	10
Curtailments	-17	-4	-49	-6
Settlements	8	0	8	0
Net periodic benefit cost	49	150	153	448
Other Postretirement Benefit Plans, Defined Benefit [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	18	28	56	76
Interest cost	27	25	84	79
Expected return on plan assets	-35	-31	-104	-94
Net amortization	-18	-13	-53	-37
Termination benefits	5	4	13	6
Curtailments	-7	-5	-33	-7
Net periodic benefit cost	($10)	$8	($37)	$23

Other_Income_Expense_Net_Other

Other (Income) Expense, Net - Other (Income) Expense, Net (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other Income and Expenses [Abstract]	'	'	'	'
Interest income	($69)	($67)	($190)	($189)
Interest expense	191	215	567	600
Exchange losses	61	11	114	278
Other, net	-325	13	-1,228	-33
Other (income) expense, net	($142)	$172	($737)	$656

Other_Income_Expense_Net_Textu

Other (Income) Expense, Net - Textual (Detail)	3 Months Ended		9 Months Ended					9 Months Ended		3 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2013	Feb. 28, 2013	Feb. 28, 2013	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014
	USD ($)	USD ($)	USD ($)	USD ($)	Venezuela [Member]	Before devaluation [Member]	After devaluation [Member]	Santen Pharmaceutical Co. Ltd. [Member]	Sirna Therapeutics Inc. [Member]	Supera [Member]
					USD ($)	Venezuela [Member]	Venezuela [Member]	USD ($)	USD ($)	USD ($)
						VEF	VEF
Component of Other Income / Expense of Nonoperating [Line Items]	'	'	'	'	'	'	'	'	'	'
Foreign currency exchange rate	'	'	'	'	'	4.3	6.3	'	'	'
Exchange losses	$61	$11	$114	$278	$140	'	'	'	'	'
AstraZeneca option exercise	'	'	741	0	'	'	'	'	'	'
Gain on disposition of technology assets	'	'	168	'	'	'	'	'	204	'
Interest paid	'	'	544	562	'	'	'	'	'	'
Gain (Loss) on Disposition of Business	'	'	396	0	'	'	'	396	'	'
Goodwill, Impairment Loss	'	'	'	'	'	'	'	'	'	$93

Taxes_on_Income_Textual_Detail

Taxes on Income - Textual (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Tax Contingency [Line Items]	'	'	'	'
Effective income tax rate	43.50%	24.60%	15.80%	14.30%
Deferred income tax benefit related to option exercise	'	'	$1,773	$532
Income tax benefit	-648	-375	-865	-618
Internal Revenue Service (IRS) [Member]	'	'	'	'
Income Tax Contingency [Line Items]	'	'	'	'
Decrease in unrecognized tax benefits resulting from prior period tax positions	'	165	'	165
Sirna Therapeutics Inc. [Member]	'	'	'	'
Income Tax Contingency [Line Items]	'	'	'	'
Income tax benefit	'	'	300	'
AstraZeneca LP [Member]	'	'	'	'
Income Tax Contingency [Line Items]	'	'	'	'
Deferred income tax benefit related to option exercise	'	'	517	'
Intercompany pricing matters [Member] | Internal Revenue Service (IRS) [Member]	'	'	'	'
Income Tax Contingency [Line Items]	'	'	'	'
Decrease in unrecognized tax benefits resulting from prior period tax positions	'	$160	'	$160

Earnings_Per_Share_Textual_Det

Earnings Per Share - Textual (Detail)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
Common shares issuable under share-based compensation plans excluded from diluted earnings per common share because the effect would have been antidilutive	5	23	4	29

Earnings_Per_Share_Calculation

Earnings Per Share - Calculations of Earnings Per Share (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Earnings Per Share [Abstract]	'		'		'		'
Net Income Attributable to Merck & Co., Inc.	$895		$1,124		$4,604		$3,623
Average common shares outstanding	2,879		2,927		2,909		2,975
Common shares issuable	32	[1]	33	[1]	33	[1]	32	[1]
Average common shares outstanding assuming dilution	2,911		2,960		2,942		3,007
Basic earnings per common share attributable to Merck & Co., Inc. common shareholders	$0.31		$0.38		$1.58		$1.22
Earnings per common share assuming dilution attributable to Merck & Co., Inc. common shareholders	$0.31		$0.38		$1.57		$1.20
[1]	Issuable primarily under share-based compensation plans.

Other_Comprehensive_Loss_Incom

Other Comprehensive (Loss) Income - Changes in AOCI by Component (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Accumulated Other Comprehensive Income (Loss), beginning balance	($2,444)		($4,760)		($2,197)		($4,682)
Other comprehensive income (loss) before reclassification adjustments, pretax	-551		-43		-1,120		92
Tax	-5		53		285		-251
Other comprehensive income (loss) before reclassification adjustments, net of taxes	-556		10		-835		-159
Reclassification adjustments, pretax	-5		64		41		205
Tax	7		-12		-7		-62
Reclassification adjustments, net of taxes	2		52		34		143
Other comprehensive income (loss), net of taxes	-554		62		-801		-16
Accumulated Other Comprehensive Income (Loss), ending balance	-2,998		-4,698		-2,998		-4,698
Derivatives [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Accumulated Other Comprehensive Income (Loss), beginning balance	27		174		132		-97
Other comprehensive income (loss) before reclassification adjustments, pretax	434		-165		277		248
Tax	-152		63		-97		-100
Other comprehensive income (loss) before reclassification adjustments, net of taxes	282		-102		180		148
Reclassification adjustments, pretax	-44		0		-48		33
Tax	16		0		17		-12
Reclassification adjustments, net of taxes	-28	[1]	0	[1]	-31	[1]	21	[1]
Other comprehensive income (loss), net of taxes	254		-102		149		169
Accumulated Other Comprehensive Income (Loss), ending balance	281		72		281		72
Investments [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Accumulated Other Comprehensive Income (Loss), beginning balance	116		-7		54		73
Other comprehensive income (loss) before reclassification adjustments, pretax	-26		55		13		11
Tax	-7		-8		-2		-16
Other comprehensive income (loss) before reclassification adjustments, net of taxes	-33		47		11		-5
Reclassification adjustments, pretax	5		-9		35		-43
Tax	-1		5		-13		11
Reclassification adjustments, net of taxes	4	[2]	-4	[2]	22	[2]	-32	[2]
Other comprehensive income (loss), net of taxes	-29		43		33		-37
Accumulated Other Comprehensive Income (Loss), ending balance	87		36		87		36
Employee Benefit Plans [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Accumulated Other Comprehensive Income (Loss), beginning balance	-1,241		-3,455		-909		-3,667
Other comprehensive income (loss) before reclassification adjustments, pretax	-715		-7		-1,287		137
Tax	226		0		449		-30
Other comprehensive income (loss) before reclassification adjustments, net of taxes	-489		-7		-838		107
Reclassification adjustments, pretax	34		73		54		215
Tax	-8		-17		-11		-61
Reclassification adjustments, net of taxes	26	[3]	56	[3]	43	[3]	154	[3]
Other comprehensive income (loss), net of taxes	-463		49		-795		261
Accumulated Other Comprehensive Income (Loss), ending balance	-1,704		-3,406		-1,704		-3,406
Cumulative Translation Adjustment [Member]	'		'		'		'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'		'		'		'
Accumulated Other Comprehensive Income (Loss), beginning balance	-1,346		-1,472		-1,474		-991
Other comprehensive income (loss) before reclassification adjustments, pretax	-244		74		-123		-304
Tax	-72		-2		-65		-105
Other comprehensive income (loss) before reclassification adjustments, net of taxes	-316		72		-188		-409
Reclassification adjustments, pretax	0		0		0		0
Tax	0		0		0		0
Reclassification adjustments, net of taxes	0		0		0		0
Other comprehensive income (loss), net of taxes	-316		72		-188		-409
Accumulated Other Comprehensive Income (Loss), ending balance	($1,662)		($1,400)		($1,662)		($1,400)
[1]	Relates to foreign currency cash flow hedges that were reclassified from AOCI to Sales.
[2]	Represents net realized (gains) losses on the sales of available-for-sale investments that were reclassified from AOCI to Other (income) expense, net.
[3]	Includes net amortization of prior service cost and actuarial gains and losses included in net periodic benefit cost (see Note 12).

Segment_Reporting_Sales_of_Com

Segment Reporting - Sales of Company's Products (Detail) (USD $)	3 Months Ended				9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Segment Reporting Information [Line Items]	'		'		'		'
Sales	$10,557		$11,032		$31,755		$32,713
Other pharmaceutical [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	1,228	[1]	1,350	[1]	3,617	[1]	4,139	[1]
Pharmaceutical segment [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	9,134		9,475		26,672		27,677
Other segments [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	1,321	[2]	1,501	[2]	4,657	[2]	4,844	[2]
Operating segments [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	10,455		10,976		31,329		32,521
Other [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	102	[3]	56	[3]	426	[3]	192	[3]
Zetia [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	660		662		1,988		1,941
Vytorin [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	369		396		1,146		1,207
Januvia [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	1,439		1,369		4,350		4,208
NuvaRing [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	186		170		531		492
Implanon [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	158		96		379		282
Follistim AQ [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	97		124		309		380
Dulera [Member] | Primary Care and Women's Health [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	124		82		328		229
PegIntron [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	84		104		300		372
Victrelis [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	27		121		132		347
Isentress [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	412		427		1,255		1,201
Cancidas [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	183		151		505		477
Invanz [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	141		130		390		360
Noxafil [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	107		75		280		212
Bridion [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	90		75		245		206
Primaxin [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	91		88		243		256
Remicade [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	604		574		1,815		1,651
Simponi [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	170		126		500		354
Cosopt/Trusopt [Member] | Hospital and Specialty [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	34		104		232		313
Emend [Member] | Oncology [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	136		123		402		373
Temodar [Member] | Oncology [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	88		162		264		596
Nasonex [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	261		297		830		1,008
Singulair [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	218		280		773		898
Clarinex [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	49		54		180		180
Cozaar/Hyzaar [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	195		238		614		760
Arcoxia [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	132		112		400		354
Fosamax [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	114		140		358		421
Propecia [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	66		71		197		206
Zocor [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	61		65		194		221
Remeron [Member] | Diversified Brands [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	47		44		137		150
Gardasil [Member] | Vaccines [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	590	[4]	665	[4]	1,382	[4]	1,438	[4]
ProQuad/M-M-R II/Varivax [Member] | Vaccines [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	421	[4]	421	[4]	1,027	[4]	1,032	[4]
RotaTeq [Member] | Vaccines [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	174	[4]	201	[4]	490	[4]	507	[4]
Zostavax [Member] | Vaccines [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	181	[4]	185	[4]	479	[4]	494	[4]
Pneumovax 23 [Member] | Vaccines [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Sales	197	[4]	193	[4]	400	[4]	412	[4]
Saphris/Sycrest [Member]	'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'
Proceeds from sale of intangible assets	'		'		$232		'
[1]	Other pharmaceutical primarily reflects sales of other human health pharmaceutical products, including products within the franchises not listed separately.
[2]	Represents the non-reportable segments of Animal Health, Consumer Care and Alliances. The Alliances segment includes revenue from the Company’s relationship with AZLP until its termination on June 30, 2014 (see Note 7). On October 1, 2014, the Company sold its Consumer Care business to Bayer (see Note 3).
[3]	Other revenues are primarily comprised of miscellaneous corporate revenues, sales related to divested products or businesses, and other supply sales not included in segment results. Other revenues in the first nine months of 2014 include $232 million received by Merck in connection with the sale of the U.S. marketing rights to Saphris (see Note 3). Other revenues also include third-party manufacturing sales, a substantial portion of which was divested in October 2013 (see Note 2).
[4]	These amounts do not reflect sales of vaccines sold in most major European markets through the Company’s joint venture, Sanofi Pasteur MSD, the results of which are reflected in Equity income from affiliates. These amounts do, however, reflect supply sales to Sanofi Pasteur MSD.

Segment_Reporting_Reconciliati

Segment Reporting - Reconciliation of Segment Profits to Income Before Taxes (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Income Before Taxes	$1,490	$1,525	$5,472	$4,320
Interest income	69	67	190	189
Interest expense	-191	-215	-567	-600
Equity income from affiliates	24	102	241	351
Depreciation and amortization	'	'	-5,118	-5,034
Research and development	-1,659	-1,660	-4,897	-5,668
Restructuring costs	-376	-870	-664	-1,144
AstraZeneca option exercise	'	'	741	0
Gain on divestiture of certain ophthalmic products	'	'	396	0
Pharmaceutical segment [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Income Before Taxes	5,772	5,983	16,475	17,022
Other segments [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Income Before Taxes	539	750	2,050	2,445
Operating segments [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Income Before Taxes	6,311	6,733	18,525	19,467
Other [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Income Before Taxes	79	-6	370	-24
Unallocated [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Interest income	69	67	190	189
Interest expense	-191	-215	-567	-600
Equity income from affiliates	-22	-67	62	-82
Depreciation and amortization	-595	-512	-1,895	-1,449
Research and development	-1,332	-1,419	-3,984	-4,928
Amortization of purchase accounting adjustments	-1,008	-1,176	-3,198	-3,545
Restructuring costs	-376	-870	-664	-1,144
AstraZeneca option exercise	0	0	741	0
Gain on divestiture of certain ophthalmic products	396	0	396	0
Other unallocated, net	-1,841	-1,010	-4,504	-3,564
Santen Pharmaceutical Co. Ltd. [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Gain on divestiture of certain ophthalmic products	'	'	$396	'