Waters (WAT) 10-Q 6 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	9 Months Ended
	Oct. 03, 2015	Oct. 30, 2015	Jul. 04, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	WATERS CORP /DE/
Entity Trading Symbol	WAT
Entity Central Index Key	1,000,697
Document Type	10-Q
Document Fiscal Period Focus	Q3
Document Period End Date	Oct. 3, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 10,641,836,000
Entity Common Stock, Shares Outstanding		81,663,790

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Oct. 03, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 459,518	$ 422,177
Investments	1,851,216	1,633,211
Accounts receivable, less allowances for doubtful accounts and sales returns of $6,651 and $7,179 at October 3, 2015 and December 31, 2014, respectively	416,311	433,616
Inventories	281,786	246,430
Other current assets	85,016	118,302
Total current assets	3,093,847	2,853,736
Property, plant and equipment, net	325,554	321,583
Intangible assets, net	222,806	232,371
Goodwill	352,151	354,838
Other assets	126,886	115,406
Total assets	4,121,244	3,877,934
Current liabilities:
Notes payable and debt	175,176	225,243
Accounts payable	61,710	65,704
Accrued employee compensation	39,809	47,198
Deferred revenue and customer advances	157,992	129,706
Accrued income taxes	5,388	15,143
Accrued warranty	13,107	13,266
Other current liabilities	82,772	85,335
Total current liabilities	535,954	581,595
Long-term liabilities:
Long-term debt	1,455,000	1,240,000
Long-term portion of retirement benefits	77,353	85,230
Long-term income tax liabilities	19,482	20,397
Other long-term liabilities	64,899	56,046
Total long-term liabilities	1,616,734	1,401,673
Total liabilities	$ 2,152,688	$ 1,983,268
Commitments and contingencies (Notes 6, 7 and 10)
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000 shares authorized, none issued at October 3, 2015 and December 31, 2014	$ 0	$ 0
Common stock, par value $0.01 per share, 400,000 shares authorized, 157,252 and 156,716 shares issued, 81,654 and 83,147 shares outstanding at October 3, 2015 and December 31, 2014, respectively	1,573	1,567
Additional paid-in capital	1,451,601	1,392,494
Retained earnings	4,712,512	4,394,513
Treasury stock, at cost, 75,598 and 73,569 shares at October 3, 2015 and December 31, 2014, respectively	(4,070,314)	(3,815,203)
Accumulated other comprehensive loss	(126,816)	(78,705)
Total stockholders' equity	1,968,556	1,894,666
Total liabilities and stockholders' equity	$ 4,121,244	$ 3,877,934

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Oct. 03, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Allowances for doubtful accounts and sales returns	$ 6,651	$ 7,179
Preferred stock, par value per share	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value per share	$ 0.01	$ 0.01
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	157,252,000	156,716,000
Common stock, shares outstanding	81,654,000	83,147,000
Treasury stock, shares	75,598,000	73,569,000

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Income Statement [Abstract]
Product sales	$ 336,933	$ 331,165	$ 971,842	$ 937,225
Service sales	163,645	162,000	483,880	468,249
Total net sales	500,578	493,165	1,455,722	1,405,474
Cost of product sales	138,014	133,868	398,168	387,646
Cost of service sales	68,790	68,354	206,589	204,148
Total cost of sales	206,804	202,222	604,757	591,794
Gross profit	293,774	290,943	850,965	813,680
Selling and administrative expenses	124,655	122,226	367,066	380,791
Research and development expenses	30,703	27,279	90,209	79,002
Purchased intangibles amortization	2,573	2,725	7,547	8,018
Operating income	135,843	138,713	386,143	345,869
Interest expense	(9,017)	(9,062)	(27,038)	(24,522)
Interest income	2,736	1,762	7,576	4,920
Income from operations before income taxes	129,562	131,413	366,681	326,267
Provision for income taxes	13,281	17,916	48,682	45,939
Net income	$ 116,281	$ 113,497	$ 317,999	$ 280,328
Net income per basic common share	$ 1.42	$ 1.36	$ 3.85	$ 3.32
Weighted-average number of basic common shares	82,036	83,663	82,552	84,375
Net income per diluted common share	$ 1.40	$ 1.34	$ 3.82	$ 3.29
Weighted-average number of diluted common shares and equivalents	82,784	84,401	83,305	85,162

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 116,281	$ 113,497	$ 317,999	$ 280,328
Foreign currency translation	(10,931)	(48,671)	(53,322)	(16,071)
Unrealized gains (losses) on investments before income taxes	1,814	(645)	2,397	91
Income tax (expense) benefit from unrealized gains (losses) on investments	(68)	42	(97)	11
Unrealized gains (losses) on investments, net of tax	1,746	(603)	2,300	102
Retirement liability adjustment before reclassifications	(511)		1,070	(931)
Retirement liability amounts reclassified to selling and administrative expenses	1,478	516	3,320	1,548
Retirement liability adjustment before income taxes	967	516	4,390	617
Income tax expense from retirement liability adjustment	(325)	(400)	(1,479)	(603)
Retirement liability adjustment, net of tax	642	116	2,911	14
Other comprehensive loss	(8,543)	(49,158)	(48,111)	(15,955)
Comprehensive income	$ 107,738	$ 64,339	$ 269,888	$ 264,373

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014
Cash flows from operating activities:
Net income	$ 317,999	$ 280,328
Adjustments to reconcile net income to net cash provided by operating activities:
Provisions for doubtful accounts on accounts receivable	766	2,051
Provisions on inventory	3,683	3,603
Stock-based compensation	24,957	24,460
Deferred income taxes	1,821	(9,151)
Depreciation	33,202	34,661
Amortization of intangibles	33,693	35,889
Building impairment		4,093
Gain on sale of building	(1,377)
Change in operating assets and liabilities, net of acquisitions:
Decrease in accounts receivable	6,121	23,588
Increase in inventories	(39,171)	(36,812)
Decrease (increase) in other current assets	2,183	(9,348)
Increase in other assets	(11,614)	(10,949)
Increase in accounts payable and other current liabilities	4,234	3,887
Increase in deferred revenue and customer advances	31,099	23,737
Decrease in other liabilities	(954)	(20,111)
Net cash provided by operating activities	406,642	349,926
Cash flows from investing activities:
Additions to property, plant, equipment and software capitalization	(72,250)	(70,437)
Business acquisitions, net of cash acquired	(9,408)	(23,672)
Payments for intellectual property licenses		(1,800)
Purchases of investments	(1,467,078)	(1,731,043)
Maturities and sales of investments	1,249,073	1,504,528
Proceeds from sale of building	5,154
Net cash used in investing activities	(294,509)	(322,424)
Cash flows from financing activities:
Proceeds from debt issuances	285,073	336,430
Payments on debt	(120,140)	(229,770)
Payments of debt issuance costs	(2,382)	(1,400)
Proceeds from stock plans	28,948	43,287
Purchases of treasury shares	(255,111)	(261,570)
Excess tax benefit related to stock option plans	5,689	8,605
Proceeds from (payments for) debt swaps and other derivative contracts	5	(366)
Net cash used in financing activities	(57,918)	(104,784)
Effect of exchange rate changes on cash and cash equivalents	(16,874)	(6,546)
Increase (decrease) in cash and cash equivalents	37,341	(83,828)
Cash and cash equivalents at beginning of period	422,177	440,796
Cash and cash equivalents at end of period	$ 459,518	$ 356,968

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Oct. 03, 2015
Basis of Presentation and Summary of Significant Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	1 Basis of Presentation and Summary of Significant Accounting Policies Waters Corporation (“Waters ® ” or the “Company”) is an analytical instrument manufacturer that primarily designs, manufactures, sells and services, through its Waters Division, high performance liquid chromatography (“HPLC”), ultra performance liquid chromatography (“UPLC ® ” and together with HPLC, referred to as “LC”) and mass spectrometry (“MS”) technology systems and support products, including chromatography columns, other consumable products and comprehensive post-warranty service plans. These systems are complementary products that are frequently employed together (“LC-MS”) and sold as integrated instrument systems using a common software platform . LC is a standard technique and is utilized in a broad range of industries to detect, identify, monitor and measure the chemical, physical and biological composition of materials, and to purify a full range of compounds. MS instruments are used in drug discovery and development, including clinical trial testing, the analysis of proteins in disease process es (known as “proteomics”), nutritional safety analysis and environmental testing. LC -MS instruments combine a liquid phase sample introduction and separation system with mass spectrometric compound identification and quantification. Through its TA Division (“TA ® ”), the Company primarily designs, manufactures, sells and services thermal analysis, rheometry and calorimetry instruments, which are used in predicting the suitability and stability of fine chemicals, pharmaceuticals, water, polymers , metals and viscous liquids for various industrial, consumer goods and healthcare products, as well as for life science research. The Company is also a developer and supplier of software-based products that interface with the Company's instruments , as well as other suppliers' instruments, and are typically purchased by customers as part of the instrument system. The Company's interim fiscal quarter typically ends on the thirteenth Saturday of each quarter. Since the Company's fiscal year end is December 31, the first and fourth fiscal quarters may have more or less than thirteen complete weeks. The Company's third fiscal quarters for 2015 and 2014 ended on October 3, 2015 and September 27, 2014 , respectively. The accompanying unaudited interim consolidated financial statements have been prepared in accordance with the instructions to the Quarterly Report on Form 10-Q and do not include all of the information and note disclosures required by generally accepted accounting principles (“GAAP”) in the United States of America. The consolidated financial statements include the accounts of the Company and its subsidiaries, most of which are wholly owned. All material inter-company balances and tra nsactions have been eliminated. The preparation of consolidated financial statements in conformity with GAAP requires the Company to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent liabilities at the dates of the financial statements. Actual amounts may differ from these estimates under different assumptions or conditions. It is management's opinion that the accompanying interim consolidated financial statements reflect all adjustments (which are normal and recurring) that are necessary for a fair statement of the results for the interim periods. The interim consolidated financial statements should be read in conjunction with the consolidated financial statem ents included in the Company's A nnual R eport on Form 10-K for the year ended December 31, 2014 , as filed with the U.S. Securities and Exchange Commission on February 27, 2015. Cash, Cash Equivalents and Investments Cash equivalents represent highly liquid investments, with original maturities of 90 days or less, while investments with longer maturities are classified as investments. The Company maintains cash balances in various operating accounts in excess of federally insured limits, and in foreign subsidiary accounts in currencies other than U.S. dollars. As of October 3, 2015 and December 31, 2014, $2,275 million out of $2,311 million and $1,971 million out of $2,055 million, respectively, of the Company's total cash, cash equivalents and investments were held by foreign subsidiaries and may be subject to material tax effects on distribution to U.S. legal entities. Property, Plant and Equipment During the three and nine months ended September 27, 2014 , the Company recorded a $4 million impairment charge related to a write-down in the fair value of a bui lding in the U.K. , which was designated as held for sale. The carrying value of the building was $4 million and was included in other current assets in the consolidated balance sheet at December 31, 2014 . During the three months ended October 3, 2015 , the Company sold the building for $5 million in cash , which resulted in a g ain on the sale of $1 million . Fair Value Measurements In accordance with the accounting standards for fair value measurements and disclosures, certain of the Company's assets and liabilities are measured at fair value on a recurring basis as of October 3, 2015 and December 31, 2014 . Fair values determined by Level 1 inputs utilize observable data , such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points for which there is little or no market data, which require the reporting entity to develop its own assumptions. The following table represents the Company's assets and liabilities measured at fair value on a recurring basis at October 3, 2015 (in thousands) : Quoted Prices in Active Significant Markets Other Significant for Identical Observable Unobservable Total at Assets Inputs Inputs October 3, 2015 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 629,048 $ - $ 629,048 $ - Corporate debt securities 1,233,772 - 1,233,772 - Time deposits 80,931 - 80,931 - Equity securities 147 - 147 - Other cash equivalents 29,000 - 29,000 - Waters 401(k) Restoration Plan assets 33,842 - 33,842 - Foreign currency exchange contracts 38 - 38 - Total $ 2,006,778 $ - $ 2,006,778 $ - Liabilities: Contingent consideration $ 4,116 $ - $ - $ 4,116 Foreign currency exchange contracts 575 - 575 - Total $ 4,691 $ - $ 575 $ 4,116 The following table represents the Company's assets and liabilities measured at fair value on a recu rring basis at December 31, 2014 (in thousands): Quoted Prices in Active Significant Markets Other Significant Total at for Identical Observable Unobservable December 31, Assets Inputs Inputs 2014 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 626,772 $ - $ 626,772 $ - Foreign government securities 24,998 - 24,998 - Corporate debt securities 984,105 - 984,105 - Time deposits 64,240 - 64,240 - Equity securities 147 - 147 - Other cash equivalents 29,000 - 29,000 - Waters 401(k) Restoration Plan assets 33,935 - 33,935 - Foreign currency exchange contracts 123 - 123 - Total $ 1,763,320 $ - $ 1,763,320 $ - Liabilities: Contingent consideration $ 3,612 $ - $ - $ 3,612 Foreign currency exchange contracts 651 - 651 - Total $ 4,263 $ - $ 651 $ 3,612 The fair values of the Company's cash equivalents, investments , 401(k) restoration plan assets and foreign currency exchange contracts are determined through market and observable sources and have been classified as Level 2 . These assets and liabilities have been initially valued at the transaction price and subsequently valued , typically utilizing third-party pricing services. The pricing services use many inputs to determine value, including reportable trades, benchmark yields, credit spreads, broker/dealer quotes, current spot rates and other industry and economic events. The Company validates the prices provided by third-party pricing services by reviewing their pricing methods and obtaining market values from other pricing sources. After completing these validation procedures, the Company did not adjust or override any fair value measurements provided by third-party pricing services as of October 3, 2015 and December 31, 2014 . Fair Value of Contingent Consideration The fair value of the Company's liability for contingent consideration related to the July 2014 acquisition of Medimass Research, Development and Service Kft . is determined using a probability-weighted discounted cash flow model, which uses significant unobservable inputs, and has been classified as Level 3. Subsequent changes in the fair value of the contingent consideration liability are recorded in the results of operations. The fair value of the contingent consideration liability associated with future earnout payments is based on several factors, including the development of future products, estimated sales of those products and a discount rate reflective of the Company's creditworthiness. A change in any of these unobservable inputs can significantly change the fair value of the contingent consideration. Although there is no contractual limit, the fair value of future contingent consideration payments was estimated to be approximately $4 million at both October 3, 2015 and December 31, 2014 , based on the Company's best estimate, as the earnout is based on future sales of certain products through 2034. There have been no changes in significant assumptions since December 31, 2014 and the change in fair value since then is primarily due to change in time value of money. Fair Value of Other Financial Instruments The Company's cash, accounts receivable, accounts payable and variable interest rate debt are recorded at cost , which approximates fair value. The carrying value of the Company's fixed interest rate debt was $450 million and $550 million at October 3, 2015 and December 31, 2014 , respectively . The fair value of the Company's fixed interest rate debt was estimated using discounted cash flow models, based on estimated current rates offered for similar debt under current market conditions for the Company. The fair value of the Company's fixed interest rate debt was estimated to be $456 million and $558 million at October 3, 2015 and December 31, 2014 , respectively , using Level 2 inputs. Derivative Transactions The Company enters into foreign currency exchange contracts to manage exposures to changes in foreign currency exchange rates on certain inter-company balances and short-term assets and liabilities. Principal hedged currenc ies include the Euro, Japanese y en, Britis h pound and Brazilian real . At October 3, 2015 and December 31, 2014 , the Company held forward foreign exchange contracts with notional amounts totaling $107 million and $110 million, respectively. T he Company's foreign currency exchange contracts included in the consolid ated balance sheets are classified as follows (in thousands): October 3, 2015 December 31, 2014 Other current assets $ 38 $ 123 Other current liabilities $ 575 $ 651 The following is a summary of the activity in cost of sales in the statements of operations related to the forward foreign exchange contracts (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Realized gains (losses) on closed contracts $ 810 $ (266) $ 5 $ (366) Unrealized losses on open contracts (71) (43) (9) (1,000) Cumulative net pre-tax gains (losses) $ 739 $ (309) $ (4) $ (1,366) Stockholders' Equity In Ma y 20 1 4 , the Company's Board of Directors authorized the Company to repurchase up to $ 75 0 million of its out standing common stock over a three -year period and authorized the extension of the May 2012 program until May 2015. During the nine months ended October 3, 2015 and September 27, 2014 , t he Company repurchased 2.0 million and 2.4 million shares of the Company's outstanding common stock at a cost of $ 249 million and $ 255 million , respectively, under the May 201 2 and May 2014 authorizations . As of October 3, 2015 , the Company re purchased an aggregate of 7.6 million shares at a cost of $750 million under the May 2012 repurchase program, which is now completed. The Company has a total of $520 million authorized for future repurchases under the May 2014 p lan . In addition, the Company repurchased $6 million and $7 million of common stock related to the vesting of restricted stock units during the nine months ended October 3, 2015 and September 27, 2014 , respectively . The Company believes that it has the financial flexibility to fund these share repurchases given current cash levels and debt borrowing capacity, as well as to invest in research, technology and business acquisitions to further grow the Company's sales and profits. Product Warranty Costs The Company accrues estimated product warranty costs at the time of sale, which are included in cost of sales in the consolidated statements of operations. While the Company engages in extensive product quality programs and processes, including actively monitoring and evaluating the quality of its component supplie r s, the Company's warranty obligation is affected by product failure rates, material usage and service delivery costs incurred in correcting a product failure. The amount of the accrued warranty liability is based on historical inform ation, such as past experience, product failure rates, number of units repaired and estimated costs of material and labor. The liability is reviewed for re asonableness at least quarterly. The following is a summary of the activity of the Company's accrued warranty liability for the nine months ended October 3, 2015 and September 27, 2014 (in thousands): Balance at Balance at Beginning Accruals for Settlements End of of Period Warranties Made Period Accrued warranty liability: October 3, 2015 $ 13,266 $ 5,834 $ (5,993) $ 13,107 September 27, 2014 $ 12,962 $ 5,292 $ (5,773) $ 12,481 Subsequent Events The Company did not have any material subsequent event s.

Marketable Securities

Marketable Securities	9 Months Ended
	Oct. 03, 2015
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash, Cash Equivalents and Short-term Investments	2 Marketable Securities The Company's marketable securities within cash equivalents and investments included in the consolidated balance sheets are detailed as follows (in thousands): October 3, 2015 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 627,630 $ 1,465 $ (47) $ 629,048 Corporate debt securities 1,233,267 895 (390) 1,233,772 Time deposits 80,931 - - 80,931 Equity securities 77 70 - 147 Total $ 1,941,905 $ 2,430 $ (437) $ 1,943,898 Amounts included in: Cash equivalents $ 92,682 $ - $ - $ 92,682 Investments 1,849,223 2,430 (437) 1,851,216 Total $ 1,941,905 $ 2,430 $ (437) $ 1,943,898 December 31, 2014 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 626,683 $ 246 $ (157) $ 626,772 Foreign government securities 24,998 - - 24,998 Corporate debt securities 984,668 125 (688) 984,105 Time deposits 64,240 - - 64,240 Equity securities 77 70 - 147 Total $ 1,700,666 $ 441 $ (845) $ 1,700,262 Amounts included in: Cash equivalents $ 67,051 $ - $ - $ 67,051 Investments 1,633,615 441 (845) 1,633,211 Total $ 1,700,666 $ 441 $ (845) $ 1,700,262 The estimated fair value of marketable debt securities by maturity date is as follows (in thousands): October 3, 2015 December 31, 2014 Due in one year or less $ 1,063,640 $ 872,872 Due after one year through three years 799,180 763,003 Total $ 1,862,820 $ 1,635,875

Inventories

Inventories	9 Months Ended
	Oct. 03, 2015
Inventory Items, Net Of Reserves Alternative [Abstract]
Inventories Disclosure	3 Inventories Inventories are classi fied as follows (in thousands): October 3, 2015 December 31, 2014 Raw materials $ 94,226 $ 84,952 Work in progress 21,814 16,749 Finished goods 165,746 144,729 Total inventories $ 281,786 $ 246,430

Acquisitions

Acquisitions	9 Months Ended
	Oct. 03, 2015
Acquisitions [Abstract]
Acquisitions	4 Acquisitions The Company accounts for business acquisitions under the accounting standards for business combinations . T he results of each acquisition have been included in the Company's consolidated results as of the acquisition date and the purchase price of an acquisition is allocated to tangible and intangible assets and assumed liabilities based on their estimated fair values. Any excess of the fair value consideration transferred over the estimated fair values of the net assets acquired is recognized as goodwill . O n May 22, 2015 , the Company acquired the net assets of the ElectroF orce ® business of the Bose Corporation (“ ElectroF orce ”) , a manufacturer of testing systems , for approximately $9 million in cash. ElectroF orce 's core business is the manufacturing of dynamic mechanical testing systems used to characterize m edical devices, biologic and e n gineered materials. The Electro F orce test instruments are based on unique motor designs that are quiet, energy-efficient, scalable and deliver high performance over a wide range of force and frequency . Electro F orce was acquired to expand the TA Division's product offering into new markets , while leveraging the technology, infrastructure and customer bases of the combined organizations. The Company has allocated $4 mil lion of the purchase price to intangible asset s comprised of technology , c ustomer relationships and trade name. The Company is amortizing the technology and customer relationships over ten years and five years, respectively. The remaining purchase price of $ 1 million was accounted for as goodwill , which is deductible for tax purposes. The principal factor that resulted in recognition of goo dwill in the acquisition of Electro F orce is that the purchase price was based, in part, on cash flow projections assuming the integration of any acquired technology, distribution channels and products with the Company's products, which is of considerably grea ter value than utilizing the acquired com pany's technology, customer access or products on a stand-alone basis. The goodwill also includes value assigned to assembled workforce, which cannot be recognized as an intangible asset. In thi s acquisition, the sellers provided the Company with customary representations, warranties and indemnification, which would be settled in the future if and when a breach of the contractual representation or warranty condition occurs. The i mpact of the acquisition of Electro F orce on the Company's revenues and net income since the acquisition date for th e nine months ended October 3, 2015 was immaterial. The fair values of the assets and liabilities acquired were determined using various income-approach valuation techniques, which use Level 3 inputs. The followin g table presents the fair values as of the acquisition date , as deter mined by the Company, of 100% of the assets and liabilities owned and recorded in connection with the acquisition of Electro F orce (in thousands): Accounts receivable and other current assets $ 1,520 Inventory 4,489 Property, plant and equipment 699 Intangible assets 3,700 Goodwill 1,118 Total assets acquired 11,526 Accrued expenses and other current liabilities 2,118 Cash consideration paid $ 9,408

Goodwill and Other Intangibles

Goodwill and Other Intangibles	9 Months Ended
	Oct. 03, 2015
Goodwill and Other Intangibles [Abstract]
Goodwill and Other Intangibles	5 Goodwill and Other Intangibles The carrying amount of goodwill was $ 352 million and $ 355 million at October 3, 2015 and December 31, 2014 , respectively. During the nine months ended October 3, 2015 , t he Company's acquisition increased goodwill by $1 million ( see Note 4) and the effect of foreign currency translation decrease d goodwill by $ 4 million . T he Company's intangible assets included in the consolidated balance sheets are detailed as follows (in thousands): October 3, 2015 December 31, 2014 Weighted- Weighted- Gross Average Gross Average Carrying Accumulated Amortization Carrying Accumulated Amortization Amount Amortization Period Amount Amortization Period Capitalized software $ 335,517 $ 202,468 7 years $ 334,280 $ 196,477 7 years Purchased intangibles 163,144 117,632 11 years 163,855 112,279 11 years Trademarks and IPR&D 13,967 - 14,095 - Licenses 5,499 3,995 6 years 5,371 3,634 6 years Patents and other intangibles 61,773 32,999 8 years 56,513 29,353 8 years Total $ 579,900 $ 357,094 8 years $ 574,114 $ 341,743 8 years During the nine months ended October 3, 2015 , the Company acquired $4 million of purchased intangibles as a result of the acquisition of Electro F orce ( see No t e 4). During the nine months ended October 3, 2015 , the effect of foreign currency translation decrease d the gross carrying value of intangible assets and accumulated amortization for intangible assets by $31 million and $18 million, respectively. A mortization expe nse fo r intangible assets was $12 million f or both the three months ended October 3, 2015 and September 27, 2014 . A mortization expe nse for intangible assets was $34 million and $36 million f or the nine months ended October 3, 2015 and September 27, 2014 , respectively . A mortization expense for intangible assets is estimated to be approximately $ 44 million per year for each of the next five year s.

Debt

Debt	9 Months Ended
	Oct. 03, 2015
Debt [Abstract]
Debt Disclosure	6 Debt In Ju ne 201 3 , the Company entered into a credit agreement that provides for a $ 1. 1 b illion revolving facility and a $ 3 00 million term loan facility. In April 2015, Waters entered into an amendment to th is a greement (the “Amended Credit Agreement”) . The A mended C redit A greement provides for an increase of the revolving commitments from $1.1 billion to $1.3 billion and extends the maturity of the original credit agreement from June 25, 2018 until April 23, 2020. The Company plans to use future proceeds from the revolving facility for general corporate purposes. The interest rates applicable to the Amended Credit Agreement are, at the Company's option, equal to either th e alternate base rate calculated daily (which is a rate per annum equal to the greatest of (a ) the prime rate in effect on such day, (b ) the federal funds effective rate in effect on such day plus 1/2 % per annum , or ( c ) the adjusted LIBO rate on such day (or if such day is not a business day, the immediately preceding business day) for a deposit in U.S. dollars with a maturity of one month plus 1% per annum) or the applicable 1, 2, 3 or 6 month adjusted LIBO rate, in each case, plus an interest rate margin based upon the Company's leverage ratio, which can range between 0 to 12.5 basis points for alternate base rate loans and between 80 b asis points and 1 1 7 .5 basis points for adjusted LIBO rate loans . The facility fee on the Amended C redit Agreement ranges between 7 .5 basis points and 2 0 basis points. The Amended Credit Agreement requires that the Company comply with an interest coverage ratio test of not less than 3.50:1 as of the end of any fiscal quarter for any period of four consecutive fiscal quarters and a leverage ratio test of not more than 3.5 0 :1 as of the end of any fiscal quarter . In addition, the Amended Credit Agreement includes negative covenants , affirmative covenants, representations and warranties and events of default that are customary for investment grade credit facilities . A t October 3, 2015 , $125 million of the outstanding portion of the revolving facility was classified as short-term liabilities in the consolidated balance sheet due to the fact that the Company expects to repay this portion of the borrowing under the revolving line of credit within the next twelve months . The remaining $705 million of the outstanding portion of the revolving facility was classified as long-term liabilities in the consolidated balance sheet, as this portion is not expected to be repaid within the next twelve months. As of October 3, 2015 and December 31, 2014 , the Company had a total of $500 million and $600 million of outstanding senior unsecured notes , respectively . Interest on the fixed rate senior unsecured notes is payable semi-annually each year. Interest on the floating rate senior unsecured notes is payable quarterly. The Company may prepay all or some of the senior unsecured notes at any time in an amount not less than 10% of the aggregate principal amount outstanding, plus the applicable make-whole amount or prepayment premium for Series H senior unsecured notes . In the event of a change in control of the Company (as defined in the note purchase agreement), the Company may be required to prepay the senior unsecured notes at a price equal to 100% of the principal amount thereof, plus accrued and unpaid interest. These senior unsecured notes require that the Company comply with an interest coverage ratio test of not less than 3.50:1 for any period of four consecuti ve fiscal quarters and a leverage ratio test of not more than 3.50:1 as of the end of any fiscal quarter . In addition, these senior unsecured notes include customary negative covenants , affirmative covenants, representations and warranties and events of default. T he Company had the following outstanding debt a t October 3, 2015 and December 31, 2014 (in thousands) : October 3, 2015 December 31, 2014 Foreign subsidiary lines of credit $ 176 $ 243 Senior unsecured notes - Series A - 3.75%, due February 2015 - 100,000 Senior unsecured notes - Series C - 2.50%, due March 2016 50,000 - Credit agreements 125,000 125,000 Total notes payable and debt 175,176 225,243 Senior unsecured notes - Series B - 5.00%, due February 2020 100,000 100,000 Senior unsecured notes - Series C - 2.50%, due March 2016 - 50,000 Senior unsecured notes - Series D - 3.22%, due March 2018 100,000 100,000 Senior unsecured notes - Series E - 3.97%, due March 2021 50,000 50,000 Senior unsecured notes - Series F - 3.40%, due June 2021 100,000 100,000 Senior unsecured notes - Series G - 3.92%, due June 2024 50,000 50,000 Senior unsecured notes - Series H - floating rate*, due June 2024 50,000 50,000 Credit agreements 1,005,000 740,000 Total long-term debt 1,455,000 1,240,000 Total debt $ 1,630,176 $ 1,465,243 * Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%. As of October 3, 2015 and December 31, 2014 , the Company had a total amount available to borrow of $ 468 million and $ 533 million, respectively, after outstanding letters of credit , under the c redit a greement s . The weighted-average interest rates applicable to the senior unsecured notes and c redit a greement borrowings collectively were 2.06% and 2.31% at October 3, 2015 and December 31, 2014 , respectively. As of October 3, 2015 , the Company was in compliance with all debt covenants. The Company and its foreign subsidiaries also had available short-term lines of credit totaling $ 98 million and $ 88 million at October 3, 2015 and December 31, 2014 , respectively, for the purpose of short-term borrowing and issuance of commercial guarantees. At October 3, 2015 and December 31, 2014 , the weighted-average interest rate s applicable to these short-term borrowings were 2.00% and 1.48% , respectively.

Income Taxes

Income Taxes	9 Months Ended
	Oct. 03, 2015
Income Taxes [Abstract]
Income Taxes	7 Income Taxes The Company's effective tax rate was 10.3% and 13.6% for the three months ended October 3, 2015 and September 27, 2014 , respectively . The Company's effective tax rate was 13.3% and 14.1% for the nine months ended October 3, 2015 and September 27, 2014 , respectively . The difference s between the effective tax rates for 2015 as compared to 2014 were primarily attributable to differences in the proportionate amounts of pre-tax income recognized in jurisdictions with different effective tax rates , and the recognition of a $2 million discrete benefit for additional U.K. tax credits in the three months ended October 3, 2015 . In the third quarter of 2015, t he Company entered into a new agreement with Singapore tax authorities that extended a 0% contractual tax rate through March 20 21. The contractual tax rate is dependent upon achievement of certain contractual milestones , which the Company expects to meet . The current statutory tax rate in Singapore is 17%. The Company accounts for its uncertain tax return reporting positions in accordan ce with the accounting standards for income taxes, which require financial statement reporting of the expected future tax consequences of uncertain tax reporting positions on the presumption that all concerned tax authoriti es possess full knowledge of those reporting positions, as well as all of the pertinent facts and circumstances, but prohibit any discounting of u nrecognized tax benefits associated with those reporting positions for the time value of money. The following is a summary of the activity of the Company's unrecognized tax benefits for the nine months ended October 3, 2015 and September 27, 2014 (in thousands): October 3, 2015 September 27, 2014 Balance at the beginning of the period $ 19,596 $ 24,716 Net changes in uncertain tax benefits (861) (3,268) Balance at the end of the period $ 18,735 $ 21,448 With limited exceptions, the Company is no longer subject to tax audit examinations in significant jurisdictions for the years ended on or before December 31, 20 11. However, carryforward attributes that were generated in years beginning on or before January 1, 201 2 may still be adjusted upon examination by tax authorities if the attributes are utilized. The Company continuously monitors the lapsing of statutes of limitations on potential tax assessments for related changes in the measurement of unrecognized tax benefits, related net interest and penalties, and deferred tax assets and liabilities. As of October 3, 2015 , the Company expects to record additional reductions in the measurement of its unrecognized tax benefits and related net interest and penalties of approximately $ 5 million within the next twelve months due to the lapsing of statutes of limitations on potential tax assessments. The Company does not expect to record any other material reductions in the measurement of its unrecognized tax benefits within the next twelve months.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Oct. 03, 2015
Stock-Based Compensation [Abstract]
Stock-Based Compensation	8 Stock-Based Compensation The Company maintains various shareholder-approved, stock-based compensation plans which allow for the issuance of incentive or non-qualified stock options, stock appreciation rights, restricted stock or other types of awards (e.g. restricted stock units). The Company accounts for stock-based compensation costs in accordance with the accounting standard s for stock-based compensation, which require that all share-based payments to employees be recognized in the statements of operations based on their grant date fair values. The Company recognizes the expense using the straight-line attribution method. The stock-based compensation expense recognized in the consolidated statements of operations is based on awards that ultimately are expected to vest; therefore, the amount of expense has been reduced for estimated forfeitures. The stock-based compensation accounting standard s require forfeitures to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Forfeitures were estimated based on historical experience. If actual results differ significantly from these estimates, stock-based compensation expense and the Company's results of operations could be materially impacted. In addition, if the Company employs different assum ptions in the application of the s e standard s , the compensation expense that the Company records in the future periods may differ significantly from what the Company has recorded in the current period. The consolidated statements of operations for the three and nine months ended October 3, 2015 and September 27, 2014 include the following stock-based compensation expense related to stock option awards, restricted stock, restricted stock unit awards and the employee stock purch ase plan (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Cost of sales $ 668 $ 633 $ 1,990 $ 2,061 Selling and administrative expenses 6,626 6,355 19,686 19,345 Research and development expenses 1,053 1,119 3,281 3,054 Total stock-based compensation $ 8,347 $ 8,107 $ 24,957 $ 24,460 Stock Options In determining the fair value of the stock options, the Company makes a variety of assumptions and estimates, including volatility measures, expected yields and expected stock option lives. The fair value of each option grant was estimated on the date of grant using the Black- Scholes option pricing model. The Company uses implied volatility on its publicly - traded options as the basis for its estimate of expected volatility. The Company believes that implied volatility is the most appropriate indicator of expected volatility because it is generally reflective of historical volatility and expectations of how future volatility will differ from historical volatility. The expected life assumption for grants is based on historical experience for the population of non-qualified stock option exercises . The risk-free interest rate is the yield currently available on U.S. Treasury zero-coupon issues with a remaining term approximating the expected term used as the input to the Black- Scholes model. The relevant data used to determine the value of the stock options granted during the nine months ended October 3, 2015 and September 27, 2014 are as follows: Nine Months Ended Options Issued and Significant Assumptions Used to Estimate Option Fair Values October 3, 2015 September 27, 2014 Options issued in thousands 115 32 Risk-free interest rate 1.4% 1.9% Expected life in years 4 4 Expected volatility 0.291 0.245 Expected dividends - - Nine Months Ended Weighted-Average Exercise Price and Fair Value of Options on the Date of Grant October 3, 2015 September 27, 2014 Exercise price $ 121.33 $ 99.22 Fair value $ 30.85 $ 22.38 T he following table summarizes stock option activity for the plans for the nine months ended October 3, 2015 (in thousands, except per share data): Number of Shares Price per Share Weighted-Average Exercise Price Outstanding at December 31, 2014 3,280 $ 37.84 to $ 113.36 $ 82.85 Granted 115 $ 113.88 to $ 134.37 $ 121.33 Exercised (342) $ 37.84 to $ 98.21 $ 74.44 Canceled (72) $ 79.05 to $ 87.06 $ 83.25 Outstanding at October 3, 2015 2,981 $ 38.09 to $ 134.37 $ 85.29 Restricted Stock During the nine months ended October 3, 2015 , the Company granted ten thousand shares of restricted stock. The fair value of these awards on the grant date was $ 113.88 per share . Restricted Stock Units The following table summarizes the unvested restricted stock unit award activity for the nine months ended October 3, 2015 (in thousands, except for per share amounts): Shares Weighted-Average Price Unvested at December 31, 2014 533 $ 94.38 Granted 150 $ 119.46 Vested (144) $ 85.40 Forfeited (12) $ 99.75 Unvested at October 3, 2015 527 $ 103.85 Restricted stock units are generally granted annually in February and vest in equal annual insta llments over a five-year period.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Oct. 03, 2015
Earnings Per Share [Abstract]
Earnings Per Share	9 Earnings Per Share Basic and diluted earnings per share (“EPS”) calculations are detailed as follows (in th ousands, except per share data): Three Months Ended October 3, 2015 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 116,281 82,036 $ 1.42 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 748 (0.02) Net income per diluted common share $ 116,281 82,784 $ 1.40 Three Months Ended September 27, 2014 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 113,497 83,663 $ 1.36 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 738 (0.02) Net income per diluted common share $ 113,497 84,401 $ 1.34 Nine Months Ended October 3, 2015 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 317,999 82,552 $ 3.85 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 753 (0.03) Net income per diluted common share $ 317,999 83,305 $ 3.82 Nine Months Ended September 27, 2014 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 280,328 84,375 $ 3.32 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 787 (0.03) Net income per diluted common share $ 280,328 85,162 $ 3.29 For t he three and nine months ended October 3, 2015 , the Company had 0.6 million and 0.7 million stock options that were antidilutive , respectively, due to having higher exercise prices than the Company's average stock price during the period. For both t he three and nine months ended September 27, 2014 , the Company had 0.5 million stock options that were antidilutive . These securities were not included in the computation of diluted EPS. The effect of dilutive securities was calculated using the treasury stock method.

Retirement Plans

Retirement Plans	9 Months Ended
	Oct. 03, 2015
Retirement Plans [Abstract]
Retirement Plans	10 Retirement Plans The Company sponsors various retirement plans. The summary of the components of net periodic pension costs for the plans for the three and nine months ended October 3, 2015 and September 27, 2014 is as follows (in thousands): Three Months Ended October 3, 2015 September 27, 2014 U.S. U.S. Retiree Non-U.S. U.S. U.S. Retiree Non-U.S. Pension Healthcare Pension Pension Healthcare Pension Plans Plan Plans Plans Plan Plans Service cost $ - $ (91) $ 1,337 $ - $ 196 $ 1,212 Interest cost 1,570 116 402 1,623 111 592 Expected return on plan assets (2,223) (129) (410) (2,179) (112) (392) Net amortization: Prior service cost (credit) - - 14 - (13) (47) Net actuarial loss (gain) 1,101 - 273 692 (18) 97 Net periodic pension cost (benefit) $ 448 $ (104) $ 1,616 $ 136 $ 164 $ 1,462 Nine Months Ended October 3, 2015 September 27, 2014 U.S. U.S. Retiree Non-U.S. U.S. U.S. Retiree Non-U.S. Pension Healthcare Pension Pension Healthcare Pension Plans Plan Plans Plans Plan Plans Service cost $ - $ 433 $ 4,011 $ - $ 594 $ 3,636 Interest cost 4,596 352 1,206 4,813 347 1,776 Expected return on plan assets (6,859) (373) (1,230) (6,795) (326) (1,176) Net amortization: Prior service cost (credit) - - 42 - (39) (141) Net actuarial loss (gain) 2,459 - 819 1,662 (26) 291 Net periodic pension cost (benefit) $ 196 $ 412 $ 4,848 $ (320) $ 550 $ 4,386 During the nine months ended October 3, 2015 , the Company contributed $ 4 million to the Company's U.S. pension plans. During fiscal year 2015 , the Company expects to contribute a total of approximately $ 6 million to $ 11 million to the Company's defined benefit plans.

Business Segment Information

Business Segment Information	9 Months Ended
	Oct. 03, 2015
Business Segment Information [Abstract]
Business Segment Information	11 Business Segment Information The Company's business activities, for which discrete financial information is available, are regularly reviewed and evaluated by the chief operating decision maker . As a result of this evaluation, the Company determined that it has two operating segments: Waters Division and TA Division. Waters Division is primarily in the business of designing, manufacturing, distributing and servicing LC and MS instruments, columns and other chemistry consumables that can be integrated and used along with other analytical instruments. TA Division is primarily in the business of designing, manufacturing, distributing and servicing thermal analysis, rheometry and calorimetry instruments. The Company's two divisions are its operating segments and each has similar economic characteristics; product processes; products and services; types and classes of customers; methods of distribution and regulatory environments. Because of these similarities, the two segments have been aggregated into one reporting segment for financial statement purposes. Please refer to the consolidated financial statements for financial information regarding the one reportable segment of the Company. Net sales for the Company's products and services are as follows for the three and nine months ended October 3, 2015 and September 27, 2014 (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Product net sales: Waters instrument systems $ 219,196 $ 213,122 $ 625,276 $ 595,670 Chemistry 78,173 77,853 234,095 229,633 TA instrument systems 39,564 40,190 112,471 111,922 Total product sales 336,933 331,165 971,842 937,225 Service net sales: Waters service 148,206 146,038 438,104 423,155 TA service 15,439 15,962 45,776 45,094 Total service sales 163,645 162,000 483,880 468,249 Total net sales $ 500,578 $ 493,165 $ 1,455,722 $ 1,405,474

Recent Accounting Standard Chan

Recent Accounting Standard Changes and Developments	9 Months Ended
	Oct. 03, 2015
Recent Accounting Standard Changes and Developments [Abstract]
Recent Accounting Standard Changes and Developments	12 Recent Accounting Standard Changes and Developments Recently Issued Accounting Standards In May 2014, amended accounting guidance was issued regarding the recognition of revenue from contracts with customers. The objective of this guidance is to significantly enhance comparability and clarify principles of revenue recognition practices across entities, industries, jurisdictions and capital markets. This guidance was originally effective for annual and interim reporting periods beginning after December 15, 2016; however, the Financial Accounting Standards Board has amended the standard in August 2015 to delay the effective period by one year. Adoption prior to December 15, 2016 is not permitted. The Company is currently evaluating its adoption method and the potential impact that the adoption of this standard will have on the Company's financial p osition, results of operations and cash flows. In April 2015, accounting guidance was issued which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability. Subsequently, the S ecurities and E xchange C ommission staff announced that it will not object when debt issuance costs related to a revolving debt arrangement are presented as an asset regardless of whether or not there is an outstanding balance on the revolving debt arrangement. This guidance is effective for annual and interim reporting periods beginning after December 15, 2015 and early adoption is permitted. The Company is currently evaluating the potential impact that the adoption of this standard will have on the Company's financial position, results of operations and cash flows . In the third quarter of 2015 , accounting guidance was issued which clarifies the measurement of inventory. The new guidance requires inventory to be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. This guidance is effective for annual and interim periods beginn ing after December 15, 2016. The Company is currently evaluating the potential impact that the adoption of this standard will have on the Company's financial position, results of operations and cash flows.

Basis of Presentation and Sum19

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Oct. 03, 2015
Basis of Presentation and Summary of Significant Accounting Policies (Policies) [Abstract]
Nature of Operations	Waters Corporation (“Waters ® ” or the “Company”) is an analytical instrument manufacturer that primarily designs, manufactures, sells and services, through its Waters Division, high performance liquid chromatography (“HPLC”), ultra performance liquid chromatography (“UPLC ® ” and together with HPLC, referred to as “LC”) and mass spectrometry (“MS”) technology systems and support products, including chromatography columns, other consumable products and comprehensive post-warranty service plans. These systems are complementary products that are frequently employed together (“LC-MS”) and sold as integrated instrument systems using a common software platform . LC is a standard technique and is utilized in a broad range of industries to detect, identify, monitor and measure the chemical, physical and biological composition of materials, and to purify a full range of compounds. MS instruments are used in drug discovery and development, including clinical trial testing, the analysis of proteins in disease process es (known as “proteomics”), nutritional safety analysis and environmental testing. LC -MS instruments combine a liquid phase sample introduction and separation system with mass spectrometric compound identification and quantification. Through its TA Division (“TA ® ”), the Company primarily designs, manufactures, sells and services thermal analysis, rheometry and calorimetry instruments, which are used in predicting the suitability and stability of fine chemicals, pharmaceuticals, water, polymers , metals and viscous liquids for various industrial, consumer goods and healthcare products, as well as for life science research. The Company is also a developer and supplier of software-based products that interface with the Company's instruments , as well as other suppliers' instruments, and are typically purchased by customers as part of the instrument system.
Fiscal Period Description	The Company's interim fiscal quarter typically ends on the thirteenth Saturday of each quarter. Since the Company's fiscal year end is December 31, the first and fourth fiscal quarters may have more or less than thirteen complete weeks. The Company's third fiscal quarters for 2015 and 2014 ended on October 3, 2015 and September 27, 2014 , respectively.
Basis of Accounting	The accompanying unaudited interim consolidated financial statements have been prepared in accordance with the instructions to the Quarterly Report on Form 10-Q and do not include all of the information and note disclosures required by generally accepted accounting principles (“GAAP”) in the United States of America. It is management's opinion that the accompanying interim consolidated financial statements reflect all adjustments (which are normal and recurring) that are necessary for a fair statement of the results for the interim periods. The interim consolidated financial statements should be read in conjunction with the consolidated financial statem ents included in the Company's A nnual R eport on Form 10-K for the year ended December 31, 2014 , as filed with the U.S. Securities and Exchange Commission on February 27, 2015.
Consolidation Policy	The consolidated financial statements include the accounts of the Company and its subsidiaries, most of which are wholly owned. All material inter-company balances and tra nsactions have been eliminated.
Use of Estimates	The preparation of consolidated financial statements in conformity with GAAP requires the Company to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent liabilities at the dates of the financial statements. Actual amounts may differ from these estimates under different assumptions or conditions.
Cash, Cash Equivalents and Investments Policy	Cash equivalents represent highly liquid investments, with original maturities of 90 days or less, while investments with longer maturities are classified as investments.
Fair Value Measurements Policy	Fair Value Measurements In accordance with the accounting standards for fair value measurements and disclosures, certain of the Company's assets and liabilities are measured at fair value on a recurring basis as of October 3, 2015 and December 31, 2014 . Fair values determined by Level 1 inputs utilize observable data , such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points for which there is little or no market data, which require the reporting entity to develop its own assumptions. Fair Value of Other Financial Instruments The Company's cash, accounts receivable, accounts payable and variable interest rate debt are recorded at cost , which approximates fair value.
Product Warranty Policy	Product Warranty Costs The Company accrues estimated product warranty costs at the time of sale, which are included in cost of sales in the consolidated statements of operations. While the Company engages in extensive product quality programs and processes, including actively monitoring and evaluating the quality of its component supplie r s, the Company's warranty obligation is affected by product failure rates, material usage and service delivery costs incurred in correcting a product failure. The amount of the accrued warranty liability is based on historical inform ation, such as past experience, product failure rates, number of units repaired and estimated costs of material and labor. The liability is reviewed for re asonableness at least quarterly.

Acquisitions (Policies)

Acquisitions (Policies)	9 Months Ended
	Oct. 03, 2015
Acquisitions [Abstract]
Business Combinations Policy	The Company accounts for business acquisitions under the accounting standards for business combinations . T he results of each acquisition have been included in the Company's consolidated results as of the acquisition date and the purchase price of an acquisition is allocated to tangible and intangible assets and assumed liabilities based on their estimated fair values. Any excess of the fair value consideration transferred over the estimated fair values of the net assets acquired is recognized as goodwill .

Income Taxes (Policies)

Income Taxes (Policies)	9 Months Ended
	Oct. 03, 2015
Income Taxes [Abstract]
Uncertain Income Tax Reporting Positions Policy	The Company accounts for its uncertain tax return reporting positions in accordan ce with the accounting standards for income taxes, which require financial statement reporting of the expected future tax consequences of uncertain tax reporting positions on the presumption that all concerned tax authoriti es possess full knowledge of those reporting positions, as well as all of the pertinent facts and circumstances, but prohibit any discounting of u nrecognized tax benefits associated with those reporting positions for the time value of money.

Stock-Based Compensation (Polic

Stock-Based Compensation (Policies)	9 Months Ended
	Oct. 03, 2015
Stock-Based Compensation [Abstract]
Stock-Based Compensation Policy	The Company accounts for stock-based compensation costs in accordance with the accounting standard s for stock-based compensation, which require that all share-based payments to employees be recognized in the statements of operations based on their grant date fair values. The Company recognizes the expense using the straight-line attribution method. The stock-based compensation expense recognized in the consolidated statements of operations is based on awards that ultimately are expected to vest; therefore, the amount of expense has been reduced for estimated forfeitures. The stock-based compensation accounting standard s require forfeitures to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Forfeitures were estimated based on historical experience. If actual results differ significantly from these estimates, stock-based compensation expense and the Company's results of operations could be materially impacted. In addition, if the Company employs different assum ptions in the application of the s e standard s , the compensation expense that the Company records in the future periods may differ significantly from what the Company has recorded in the current period. Stock Options In determining the fair value of the stock options, the Company makes a variety of assumptions and estimates, including volatility measures, expected yields and expected stock option lives. The fair value of each option grant was estimated on the date of grant using the Black- Scholes option pricing model. The Company uses implied volatility on its publicly - traded options as the basis for its estimate of expected volatility. The Company believes that implied volatility is the most appropriate indicator of expected volatility because it is generally reflective of historical volatility and expectations of how future volatility will differ from historical volatility. The expected life assumption for grants is based on historical experience for the population of non-qualified stock option exercises . The risk-free interest rate is the yield currently available on U.S. Treasury zero-coupon issues with a remaining term approximating the expected term used as the input to the Black- Scholes model.

Earnings Per Share (Policies)

Earnings Per Share (Policies)	9 Months Ended
	Oct. 03, 2015
Earnings Per Share [Abstract]
Earnings Per Share Policy	The effect of dilutive securities was calculated using the treasury stock method.

Recent Accounting Standard Ch24

Recent Accounting Standard Changes and Developments (Policies)	9 Months Ended
	Oct. 03, 2015
Recent Accounting Standard Changes and Developments [Abstract]
New Accounting Pronouncements	Recently Issued Accounting Standards In May 2014, amended accounting guidance was issued regarding the recognition of revenue from contracts with customers. The objective of this guidance is to significantly enhance comparability and clarify principles of revenue recognition practices across entities, industries, jurisdictions and capital markets. This guidance was originally effective for annual and interim reporting periods beginning after December 15, 2016; however, the Financial Accounting Standards Board has amended the standard in August 2015 to delay the effective period by one year. Adoption prior to December 15, 2016 is not permitted. The Company is currently evaluating its adoption method and the potential impact that the adoption of this standard will have on the Company's financial p osition, results of operations and cash flows. In April 2015, accounting guidance was issued which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability. Subsequently, the S ecurities and E xchange C ommission staff announced that it will not object when debt issuance costs related to a revolving debt arrangement are presented as an asset regardless of whether or not there is an outstanding balance on the revolving debt arrangement. This guidance is effective for annual and interim reporting periods beginning after December 15, 2015 and early adoption is permitted. The Company is currently evaluating the potential impact that the adoption of this standard will have on the Company's financial position, results of operations and cash flows . In the third quarter of 2015 , accounting guidance was issued which clarifies the measurement of inventory. The new guidance requires inventory to be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. This guidance is effective for annual and interim periods beginn ing after December 15, 2016. The Company is currently evaluating the potential impact that the adoption of this standard will have on the Company's financial position, results of operations and cash flows.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies (Tables)	9 Months Ended
	Oct. 03, 2015
Fair Value of Assets and Liabilities Measured on a Recurring Basis [Abstract]
Fair Value of Assets and Liabilities Measured on a Recurring Basis	The following table represents the Company's assets and liabilities measured at fair value on a recurring basis at October 3, 2015 (in thousands) : Quoted Prices in Active Significant Markets Other Significant for Identical Observable Unobservable Total at Assets Inputs Inputs October 3, 2015 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 629,048 $ - $ 629,048 $ - Corporate debt securities 1,233,772 - 1,233,772 - Time deposits 80,931 - 80,931 - Equity securities 147 - 147 - Other cash equivalents 29,000 - 29,000 - Waters 401(k) Restoration Plan assets 33,842 - 33,842 - Foreign currency exchange contracts 38 - 38 - Total $ 2,006,778 $ - $ 2,006,778 $ - Liabilities: Contingent consideration $ 4,116 $ - $ - $ 4,116 Foreign currency exchange contracts 575 - 575 - Total $ 4,691 $ - $ 575 $ 4,116 The following table represents the Company's assets and liabilities measured at fair value on a recu rring basis at December 31, 2014 (in thousands): Quoted Prices in Active Significant Markets Other Significant Total at for Identical Observable Unobservable December 31, Assets Inputs Inputs 2014 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 626,772 $ - $ 626,772 $ - Foreign government securities 24,998 - 24,998 - Corporate debt securities 984,105 - 984,105 - Time deposits 64,240 - 64,240 - Equity securities 147 - 147 - Other cash equivalents 29,000 - 29,000 - Waters 401(k) Restoration Plan assets 33,935 - 33,935 - Foreign currency exchange contracts 123 - 123 - Total $ 1,763,320 $ - $ 1,763,320 $ - Liabilities: Contingent consideration $ 3,612 $ - $ - $ 3,612 Foreign currency exchange contracts 651 - 651 - Total $ 4,263 $ - $ 651 $ 3,612
Summary of Derivative Instruments by Risk Exposure [Abstract]
Gains (Losses) on Foreign Currency Exchange Contracts	The following is a summary of the activity in cost of sales in the statements of operations related to the forward foreign exchange contracts (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Realized gains (losses) on closed contracts $ 810 $ (266) $ 5 $ (366) Unrealized losses on open contracts (71) (43) (9) (1,000) Cumulative net pre-tax gains (losses) $ 739 $ (309) $ (4) $ (1,366)
Fair Value of Forward Foreign Exchange Contracts	T he Company's foreign currency exchange contracts included in the consolid ated balance sheets are classified as follows (in thousands): October 3, 2015 December 31, 2014 Other current assets $ 38 $ 123 Other current liabilities $ 575 $ 651
Warranty Accrual Roll Forward [Abstract]
Warranty Accrual Roll Forward	The following is a summary of the activity of the Company's accrued warranty liability for the nine months ended October 3, 2015 and September 27, 2014 (in thousands): Balance at Balance at Beginning Accruals for Settlements End of of Period Warranties Made Period Accrued warranty liability: October 3, 2015 $ 13,266 $ 5,834 $ (5,993) $ 13,107 September 27, 2014 $ 12,962 $ 5,292 $ (5,773) $ 12,481

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Oct. 03, 2015
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Schedule of Cash, Cash Equivalents and Short-term Investments	The Company's marketable securities within cash equivalents and investments included in the consolidated balance sheets are detailed as follows (in thousands): October 3, 2015 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 627,630 $ 1,465 $ (47) $ 629,048 Corporate debt securities 1,233,267 895 (390) 1,233,772 Time deposits 80,931 - - 80,931 Equity securities 77 70 - 147 Total $ 1,941,905 $ 2,430 $ (437) $ 1,943,898 Amounts included in: Cash equivalents $ 92,682 $ - $ - $ 92,682 Investments 1,849,223 2,430 (437) 1,851,216 Total $ 1,941,905 $ 2,430 $ (437) $ 1,943,898 December 31, 2014 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 626,683 $ 246 $ (157) $ 626,772 Foreign government securities 24,998 - - 24,998 Corporate debt securities 984,668 125 (688) 984,105 Time deposits 64,240 - - 64,240 Equity securities 77 70 - 147 Total $ 1,700,666 $ 441 $ (845) $ 1,700,262 Amounts included in: Cash equivalents $ 67,051 $ - $ - $ 67,051 Investments 1,633,615 441 (845) 1,633,211 Total $ 1,700,666 $ 441 $ (845) $ 1,700,262
Investments Classified by Contractual Maturity Date	The estimated fair value of marketable debt securities by maturity date is as follows (in thousands): October 3, 2015 December 31, 2014 Due in one year or less $ 1,063,640 $ 872,872 Due after one year through three years 799,180 763,003 Total $ 1,862,820 $ 1,635,875

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Oct. 03, 2015
Inventory Items, Net Of Reserves Alternative [Abstract]
Inventory, Net of Reserves	Inventories are classi fied as follows (in thousands): October 3, 2015 December 31, 2014 Raw materials $ 94,226 $ 84,952 Work in progress 21,814 16,749 Finished goods 165,746 144,729 Total inventories $ 281,786 $ 246,430

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Oct. 03, 2015
Acquisitions [Abstract]
Acquired Assets and Liabilities	The fair values of the assets and liabilities acquired were determined using various income-approach valuation techniques, which use Level 3 inputs. The followin g table presents the fair values as of the acquisition date , as deter mined by the Company, of 100% of the assets and liabilities owned and recorded in connection with the acquisition of Electro F orce (in thousands): Accounts receivable and other current assets $ 1,520 Inventory 4,489 Property, plant and equipment 699 Intangible assets 3,700 Goodwill 1,118 Total assets acquired 11,526 Accrued expenses and other current liabilities 2,118 Cash consideration paid $ 9,408

Goodwill and Other Intangibles

Goodwill and Other Intangibles (Tables)	9 Months Ended
	Oct. 03, 2015
Goodwill and Other Intangibles [Abstract]
Schedule of Intangible Assets by Major Class	T he Company's intangible assets included in the consolidated balance sheets are detailed as follows (in thousands): October 3, 2015 December 31, 2014 Weighted- Weighted- Gross Average Gross Average Carrying Accumulated Amortization Carrying Accumulated Amortization Amount Amortization Period Amount Amortization Period Capitalized software $ 335,517 $ 202,468 7 years $ 334,280 $ 196,477 7 years Purchased intangibles 163,144 117,632 11 years 163,855 112,279 11 years Trademarks and IPR&D 13,967 - 14,095 - Licenses 5,499 3,995 6 years 5,371 3,634 6 years Patents and other intangibles 61,773 32,999 8 years 56,513 29,353 8 years Total $ 579,900 $ 357,094 8 years $ 574,114 $ 341,743 8 years

Debt (Tables)

Debt (Tables)	9 Months Ended
	Oct. 03, 2015
Debt [Abstract]
Schedule of Outstanding Debt	T he Company had the following outstanding debt a t October 3, 2015 and December 31, 2014 (in thousands) : October 3, 2015 December 31, 2014 Foreign subsidiary lines of credit $ 176 $ 243 Senior unsecured notes - Series A - 3.75%, due February 2015 - 100,000 Senior unsecured notes - Series C - 2.50%, due March 2016 50,000 - Credit agreements 125,000 125,000 Total notes payable and debt 175,176 225,243 Senior unsecured notes - Series B - 5.00%, due February 2020 100,000 100,000 Senior unsecured notes - Series C - 2.50%, due March 2016 - 50,000 Senior unsecured notes - Series D - 3.22%, due March 2018 100,000 100,000 Senior unsecured notes - Series E - 3.97%, due March 2021 50,000 50,000 Senior unsecured notes - Series F - 3.40%, due June 2021 100,000 100,000 Senior unsecured notes - Series G - 3.92%, due June 2024 50,000 50,000 Senior unsecured notes - Series H - floating rate*, due June 2024 50,000 50,000 Credit agreements 1,005,000 740,000 Total long-term debt 1,455,000 1,240,000 Total debt $ 1,630,176 $ 1,465,243 * Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%.

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Oct. 03, 2015
Income Taxes [Abstract]
Unrecognized Tax Benefits Roll Forward	The following is a summary of the activity of the Company's unrecognized tax benefits for the nine months ended October 3, 2015 and September 27, 2014 (in thousands): October 3, 2015 September 27, 2014 Balance at the beginning of the period $ 19,596 $ 24,716 Net changes in uncertain tax benefits (861) (3,268) Balance at the end of the period $ 18,735 $ 21,448

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Oct. 03, 2015
Stock-Based Compensation [Abstract]
Schedule of Stock-Based Compensation Expense	The consolidated statements of operations for the three and nine months ended October 3, 2015 and September 27, 2014 include the following stock-based compensation expense related to stock option awards, restricted stock, restricted stock unit awards and the employee stock purch ase plan (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Cost of sales $ 668 $ 633 $ 1,990 $ 2,061 Selling and administrative expenses 6,626 6,355 19,686 19,345 Research and development expenses 1,053 1,119 3,281 3,054 Total stock-based compensation $ 8,347 $ 8,107 $ 24,957 $ 24,460
Relevant Data Used to Determine the Value of Stock Options Granted During the Period	The relevant data used to determine the value of the stock options granted during the nine months ended October 3, 2015 and September 27, 2014 are as follows: Nine Months Ended Options Issued and Significant Assumptions Used to Estimate Option Fair Values October 3, 2015 September 27, 2014 Options issued in thousands 115 32 Risk-free interest rate 1.4% 1.9% Expected life in years 4 4 Expected volatility 0.291 0.245 Expected dividends - - Nine Months Ended Weighted-Average Exercise Price and Fair Value of Options on the Date of Grant October 3, 2015 September 27, 2014 Exercise price $ 121.33 $ 99.22 Fair value $ 30.85 $ 22.38
Stock Options Outstanding Roll Forward	T he following table summarizes stock option activity for the plans for the nine months ended October 3, 2015 (in thousands, except per share data): Number of Shares Price per Share Weighted-Average Exercise Price Outstanding at December 31, 2014 3,280 $ 37.84 to $ 113.36 $ 82.85 Granted 115 $ 113.88 to $ 134.37 $ 121.33 Exercised (342) $ 37.84 to $ 98.21 $ 74.44 Canceled (72) $ 79.05 to $ 87.06 $ 83.25 Outstanding at October 3, 2015 2,981 $ 38.09 to $ 134.37 $ 85.29
Restricted Stock Units Unvested Roll Forward	The following table summarizes the unvested restricted stock unit award activity for the nine months ended October 3, 2015 (in thousands, except for per share amounts): Shares Weighted-Average Price Unvested at December 31, 2014 533 $ 94.38 Granted 150 $ 119.46 Vested (144) $ 85.40 Forfeited (12) $ 99.75 Unvested at October 3, 2015 527 $ 103.85

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Oct. 03, 2015
Earnings Per Share Reconciliation [Abstract]
Earnings Per Share Reconciliation	Basic and diluted earnings per share (“EPS”) calculations are detailed as follows (in th ousands, except per share data): Three Months Ended October 3, 2015 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 116,281 82,036 $ 1.42 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 748 (0.02) Net income per diluted common share $ 116,281 82,784 $ 1.40 Three Months Ended September 27, 2014 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 113,497 83,663 $ 1.36 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 738 (0.02) Net income per diluted common share $ 113,497 84,401 $ 1.34 Nine Months Ended October 3, 2015 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 317,999 82,552 $ 3.85 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 753 (0.03) Net income per diluted common share $ 317,999 83,305 $ 3.82 Nine Months Ended September 27, 2014 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 280,328 84,375 $ 3.32 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 787 (0.03) Net income per diluted common share $ 280,328 85,162 $ 3.29

Retirement Plans (Tables)

Retirement Plans (Tables)	9 Months Ended
	Oct. 03, 2015
Retirement Plans [Abstract]
Defined Benefit Plan, Net Periodic Benefit Cost	The summary of the components of net periodic pension costs for the plans for the three and nine months ended October 3, 2015 and September 27, 2014 is as follows (in thousands): Three Months Ended October 3, 2015 September 27, 2014 U.S. U.S. Retiree Non-U.S. U.S. U.S. Retiree Non-U.S. Pension Healthcare Pension Pension Healthcare Pension Plans Plan Plans Plans Plan Plans Service cost $ - $ (91) $ 1,337 $ - $ 196 $ 1,212 Interest cost 1,570 116 402 1,623 111 592 Expected return on plan assets (2,223) (129) (410) (2,179) (112) (392) Net amortization: Prior service cost (credit) - - 14 - (13) (47) Net actuarial loss (gain) 1,101 - 273 692 (18) 97 Net periodic pension cost (benefit) $ 448 $ (104) $ 1,616 $ 136 $ 164 $ 1,462 Nine Months Ended October 3, 2015 September 27, 2014 U.S. U.S. Retiree Non-U.S. U.S. U.S. Retiree Non-U.S. Pension Healthcare Pension Pension Healthcare Pension Plans Plan Plans Plans Plan Plans Service cost $ - $ 433 $ 4,011 $ - $ 594 $ 3,636 Interest cost 4,596 352 1,206 4,813 347 1,776 Expected return on plan assets (6,859) (373) (1,230) (6,795) (326) (1,176) Net amortization: Prior service cost (credit) - - 42 - (39) (141) Net actuarial loss (gain) 2,459 - 819 1,662 (26) 291 Net periodic pension cost (benefit) $ 196 $ 412 $ 4,848 $ (320) $ 550 $ 4,386

Business Segment Information (T

Business Segment Information (Tables)	9 Months Ended
	Oct. 03, 2015
Business Segment Information [Abstract]
Revenue from External Customers by Products and Services	Net sales for the Company's products and services are as follows for the three and nine months ended October 3, 2015 and September 27, 2014 (in thousands): Three Months Ended Nine Months Ended October 3, 2015 September 27, 2014 October 3, 2015 September 27, 2014 Product net sales: Waters instrument systems $ 219,196 $ 213,122 $ 625,276 $ 595,670 Chemistry 78,173 77,853 234,095 229,633 TA instrument systems 39,564 40,190 112,471 111,922 Total product sales 336,933 331,165 971,842 937,225 Service net sales: Waters service 148,206 146,038 438,104 423,155 TA service 15,439 15,962 45,776 45,094 Total service sales 163,645 162,000 483,880 468,249 Total net sales $ 500,578 $ 493,165 $ 1,455,722 $ 1,405,474

Basis of Presentation and Sum36

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) shares in Millions	1 Months Ended	3 Months Ended		9 Months Ended		35 Months Ended
	May. 31, 2014	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014	Apr. 04, 2015	Dec. 31, 2014
Derivative [Line Items]
Notional amount of foreign currency exchange contracts		$ 107,000,000		$ 107,000,000			$ 110,000,000
Cumulative net pre-tax gains (losses) on foreign exchange contracts		739,000	$ (309,000)	(4,000)	$ (1,366,000)
Realized gains (losses) on foreign exchange contracts		810,000	(266,000)	5,000	(366,000)
Unrealized (losses) gains on foreign exchange contracts		(71,000)	(43,000)	(9,000)	(1,000,000)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		1,943,898,000		1,943,898,000			1,700,262,000
Other cash equivalents		29,000,000		29,000,000			29,000,000
Waters 401(k) Restoration Plan assets		33,842,000		33,842,000			33,935,000
Foreign currency exchange contract assets		38,000		38,000			123,000
Fair value of total assets measured on a recurring basis		2,006,778,000		2,006,778,000			1,763,320,000
Contingent consideration		4,116,000		4,116,000			3,612,000
Foreign currency exchange contract liabilities		575,000		575,000			651,000
Fair value of total liabilities measured on a recurring basis		4,691,000		4,691,000			4,263,000
Property, Plant and Equipment [Line Items]
Real estate impairment			4,000,000		4,000,000
Fair value of building held-for-sale							4,000,000
Proceeds from sale of building				5,154,000
Gain on sale of building				$ 1,377,000
Cash Equivalents and Investments [Line Items]
Cash equivalents description				Cash equivalents represent highly liquid investments, with original maturities of 90 days or less, while investments with longer maturities are classified as investments.
Cash, cash equivalents and investments		2,311,000,000		$ 2,311,000,000			2,055,000,000
Debt [Line Items]
Long-term debt		1,455,000,000		1,455,000,000			1,240,000,000
Warranty Accrual Roll Forward [Abstract]
Accrued warranty liability, balance at beginning of period				13,266,000	12,962,000
Accruals for warranties				5,834,000	5,292,000
Settlements made				(5,993,000)	(5,773,000)
Accrued warranty liability, balance at end of period		13,107,000	$ 12,481,000	13,107,000	$ 12,481,000
US Treasury Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		629,048,000		629,048,000			626,772,000
Foreign Government Debt Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value							24,998,000
Corporate Debt Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		1,233,772,000		1,233,772,000			984,105,000
Time Deposits
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		80,931,000		80,931,000			64,240,000
Equity Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		147,000		$ 147,000			147,000
Programs authorized by Board of Directors [Member]
Stock Repurchase Program [Line Items]
Treasury stock shares acquired				2	2.4
Treasury stock				$ 249,000,000	$ 255,000,000
Stock repurchase program remaining amount authorized for future purchases		520,000,000		520,000,000
Related To Vesting Of Restricted Stock Units [Member]
Stock Repurchase Program [Line Items]
Treasury stock				6,000,000	$ 7,000,000
May 2014 Program [Member]
Stock Repurchase Program [Line Items]
Stock repurchase program authorization amount	$ 750,000,000
Stock repurchase program period, in years	3 years
May 2012 Program [Member]
Stock Repurchase Program [Line Items]
Treasury stock shares acquired						7.6
Treasury stock						$ 750,000,000
Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Other cash equivalents		29,000,000		29,000,000			29,000,000
Waters 401(k) Restoration Plan assets		33,842,000		33,842,000			33,935,000
Foreign currency exchange contract assets		38,000		38,000			123,000
Fair value of total assets measured on a recurring basis		2,006,778,000		2,006,778,000			1,763,320,000
Foreign currency exchange contract liabilities		575,000		575,000			651,000
Fair value of total liabilities measured on a recurring basis		575,000		575,000			651,000
Significant Other Observable Inputs (Level 2) | US Treasury Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		629,048,000		629,048,000			626,772,000
Significant Other Observable Inputs (Level 2) | Foreign Government Debt Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value							24,998,000
Significant Other Observable Inputs (Level 2) | Corporate Debt Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		1,233,772,000		1,233,772,000			984,105,000
Significant Other Observable Inputs (Level 2) | Time Deposits
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		80,931,000		80,931,000			64,240,000
Significant Other Observable Inputs (Level 2) | Equity Securities
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value		147,000		147,000			147,000
Significant Unobservable Inputs (Level 3)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		4,116,000		4,116,000			3,612,000
Fair value of total liabilities measured on a recurring basis		4,116,000		4,116,000			3,612,000
Unsecured debt
Debt [Line Items]
Long-term debt		500,000,000		500,000,000			600,000,000
Unsecured debt | Fixed interest rate [Member]
Debt [Line Items]
Long-term debt		450,000,000		450,000,000			550,000,000
Fair value of debt instruments		456,000,000		456,000,000			558,000,000
Held by foreign subsidiaries [Member]
Cash Equivalents and Investments [Line Items]
Cash, cash equivalents and investments		$ 2,275,000,000		$ 2,275,000,000			$ 1,971,000,000

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Oct. 03, 2015	Dec. 31, 2014
Cash Equivalents and Investments [Line Items]
Amortized Cost	$ 1,941,905	$ 1,700,666
Unrealized Gain	2,430	441
Unrealized Loss	(437)	(845)
Fair Value	1,943,898	1,700,262
Debt securities due in one year or less	1,063,640	872,872
Debt securities due after one year through three years	799,180	763,003
Total debt securities	1,862,820	1,635,875
Cash Equivalents [Member]
Cash Equivalents and Investments [Line Items]
Amortized Cost	92,682	67,051
Fair Value	92,682	67,051
Investments [Member]
Cash Equivalents and Investments [Line Items]
Amortized Cost	1,849,223	1,633,615
Unrealized Gain	2,430	441
Unrealized Loss	(437)	(845)
Fair Value	1,851,216	1,633,211
US Treasury Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost	627,630	626,683
Unrealized Gain	1,465	246
Unrealized Loss	(47)	(157)
Fair Value	629,048	626,772
Foreign Government Debt Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost		24,998
Fair Value		24,998
Corporate Debt Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost	1,233,267	984,668
Unrealized Gain	895	125
Unrealized Loss	(390)	(688)
Fair Value	1,233,772	984,105
Time Deposits
Cash Equivalents and Investments [Line Items]
Amortized Cost	80,931	64,240
Fair Value	80,931	64,240
Equity Securities
Cash Equivalents and Investments [Line Items]
Amortized Cost	77	77
Unrealized Gain	70	70
Fair Value	$ 147	$ 147

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Oct. 03, 2015	Dec. 31, 2014
Inventory Items, Net Of Reserves Alternative [Abstract]
Raw materials	$ 94,226	$ 84,952
Work in progress	21,814	16,749
Finished goods	165,746	144,729
Total inventories	$ 281,786	$ 246,430

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Oct. 03, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 352,151	$ 354,838
Weighted-average useful life of acquired intangible assets	8 years	8 years
Pro forma effect of business acquisitions	The i mpact of the acquisition of Electro F orce on the Company's revenues and net income since the acquisition date for th e nine months ended October 3, 2015 was immaterial.
Acquisitions in 2015 [Member]
Business Acquisition [Line Items]
Accounts receivable and other current assets acquired	$ 1,520
Inventory acquired	4,489
Property, plant and equipment acquired	699
Intangible assets acquired	3,700
Goodwill	1,118
Total assets acquired	11,526
Accrued expenses and other current liabilities acquired	2,118
Cash consideration paid	$ 9,408
Acquisitions in 2015 [Member] | Unpatented Technology [Member]
Business Acquisition [Line Items]
Weighted-average useful life of acquired intangible assets	10 years
Acquisitions in 2015 [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Weighted-average useful life of acquired intangible assets	5 years

Goodwill and Other Intangible40

Goodwill and Other Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 352,151		$ 352,151		$ 354,838
Goodwill foreign currency translation adjustments			(4,000)
Intangible Assets [Line Items]
Intangible assets, gross	579,900		579,900		574,114
Intangible assets, accumulated amortization	357,094		$ 357,094		$ 341,743
Weighted-average useful life of acquired intangible assets			8 years		8 years
Intangible assets, gross foreign currency translation adjustments			$ (31,000)
Intangible assets, accumulated amortization foreign currency translation adjustments			(18,000)
Amortization expense	12,000	$ 12,000	34,000	$ 36,000
Future amortization expense, year 1	44,000		44,000
Future amortization expense, year 2	44,000		44,000
Future amortization expense, year 3	44,000		44,000
Future amortization expense, year 4	44,000		44,000
Future amortization expense, year 5	44,000		44,000
Capitalized software [Member]
Intangible Assets [Line Items]
Intangible assets, gross	335,517		335,517		$ 334,280
Intangible assets, accumulated amortization	202,468		$ 202,468		$ 196,477
Weighted-average useful life of acquired intangible assets			7 years		7 years
Purchased intangibles [Member]
Intangible Assets [Line Items]
Intangible assets, gross	163,144		$ 163,144		$ 163,855
Intangible assets, accumulated amortization	117,632		$ 117,632		$ 112,279
Weighted-average useful life of acquired intangible assets			11 years		11 years
Trademarks and IPR&D[Member]
Intangible Assets [Line Items]
Intangible assets, gross	13,967		$ 13,967		$ 14,095
Licenses [Member]
Intangible Assets [Line Items]
Intangible assets, gross	5,499		5,499		5,371
Intangible assets, accumulated amortization	3,995		$ 3,995		$ 3,634
Weighted-average useful life of acquired intangible assets			6 years		6 years
Patents and other intangibles [Member]
Intangible Assets [Line Items]
Intangible assets, gross	61,773		$ 61,773		$ 56,513
Intangible assets, accumulated amortization	32,999		$ 32,999		$ 29,353
Weighted-average useful life of acquired intangible assets			8 years		8 years
Acquisitions in 2015
Goodwill [Line Items]
Goodwill	1,118		$ 1,118
Intangible Assets [Line Items]
Intangible assets acquired	$ 3,700		$ 3,700

Debt (Details)

Debt (Details) - USD ($)		9 Months Ended
		Oct. 03, 2015	Apr. 23, 2015	Dec. 31, 2014	Jun. 25, 2013
Debt [Line Items]
Notes payable and debt		$ 175,176,000		$ 225,243,000
Long-term debt		1,455,000,000		1,240,000,000
Total debt		$ 1,630,176,000		1,465,243,000
Senior unsecured notes - Series A [Member]
Debt [Line Items]
Stated interest rate on debt instrument		3.75%
Notes payable and debt				100,000,000
Senior unsecured notes - Series B [Member]
Debt [Line Items]
Stated interest rate on debt instrument		5.00%
Long-term debt		$ 100,000,000		100,000,000
Senior unsecured notes - Series C [Member]
Debt [Line Items]
Stated interest rate on debt instrument		2.50%
Notes payable and debt		$ 50,000,000
Long-term debt				50,000,000
Senior unsecured notes - Series D [Member]
Debt [Line Items]
Stated interest rate on debt instrument		3.22%
Long-term debt		$ 100,000,000		100,000,000
Senior unsecured notes - Series E [Member]
Debt [Line Items]
Stated interest rate on debt instrument		3.97%
Long-term debt		$ 50,000,000		50,000,000
Senior unsecured notes - Series F [Member]
Debt [Line Items]
Stated interest rate on debt instrument		3.40%
Long-term debt		$ 100,000,000		100,000,000
Senior Unsecured Notes - Series G [Member]
Debt [Line Items]
Stated interest rate on debt instrument		3.92%
Long-term debt		$ 50,000,000		50,000,000
Senior Unsecured Note - Series H [Member]
Debt [Line Items]
Interest rate terms on debt		* Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%.
Long-term debt	[1]	$ 50,000,000		50,000,000
Foreign subsidiary lines of credit [Member]
Debt [Line Items]
Notes payable and debt		$ 176,000		$ 243,000
Weighted-average interest rate		2.00%		1.48%
Line of credit maximum borrowing capacity		$ 98,000,000		$ 88,000,000
Unsecured debt
Debt [Line Items]
Call feature on debt instrument		The Company may prepay all or some of the senior unsecured notes at any time in an amount not less than 10% of the aggregate principal amount outstanding, plus the applicable make-whole amount or prepayment premium for Series H senior unsecured notes. In the event of a change in control of the Company (as defined in the note purchase agreement), the Company may be required to prepay the senior unsecured notes at a price equal to 100% of the principal amount thereof, plus accrued and unpaid interest.
Debt covenant description		These senior unsecured notes require that the Company comply with an interest coverage ratio test of not less than 3.50:1 for any period of four consecutive fiscal quarters and a leverage ratio test of not more than 3.50:1 as of the end of any fiscal quarter.
Long-term debt		$ 500,000,000		600,000,000
Credit agreements
Debt [Line Items]
Interest rate terms on debt		The interest rates applicable to the Amended Credit Agreement are, at the Company’s option, equal to either the alternate base rate calculated daily (which is a rate per annum equal to the greatest of (a) the prime rate in effect on such day, (b) the federal funds effective rate in effect on such day plus 1/2% per annum, or (c) the adjusted LIBO rate on such day (or if such day is not a business day, the immediately preceding business day) for a deposit in U.S. dollars with a maturity of one month plus 1% per annum) or the applicable 1, 2, 3 or 6 month adjusted LIBO rate, in each case, plus an interest rate margin based upon the Company’s leverage ratio, which can range between 0 to 12.5 basis points for alternate base rate loans and between 80 basis points and 117.5 basis points for adjusted LIBO rate loans.
Debt facility fee		The facility fee on the Amended Credit Agreement ranges between 7.5 basis points and 20 basis points.
Debt covenant description		The Amended Credit Agreement requires that the Company comply with an interest coverage ratio test of not less than 3.50:1 as of the end of any fiscal quarter for any period of four consecutive fiscal quarters and a leverage ratio test of not more than 3.50:1 as of the end of any fiscal quarter.
Notes payable and debt		$ 125,000,000		125,000,000
Long-term debt		1,005,000,000		740,000,000
Unused borrowing capacity		468,000,000		$ 533,000,000
Credit agreements | Term loan facility [Member]
Debt [Line Items]
Face value of debt					$ 300,000,000
Credit agreements | Revolving facilities [Member]
Debt [Line Items]
Face value of debt			$ 1,300,000,000		$ 1,100,000,000
Notes payable and debt		125,000,000
Long-term debt		$ 705,000,000
Credit agreements and unsecured debt [Member]
Debt [Line Items]
Weighted-average interest rate		2.06%		2.31%
[1]	* Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%.

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Income Tax Contingency [Line Items]
Unrecognized tax benefits, balance at the beginning of the period			$ 19,596	$ 24,716
Other changes in uncertain tax benefits			(861)	(3,268)
Unrecognized tax benefits, balance at the end of the period	$ 18,735	$ 21,448	18,735	$ 21,448
Expected change in unrecognized tax benefits in the next twelve months	$ (5,000)		$ (5,000)
Income Taxes [Line Items]
Effective income tax rate	10.30%	13.60%	13.30%	14.10%
Discrete international benefit			$ 2,000
Singapore [Member]
Income Taxes [Line Items]
Marginal effective income tax rate			0.00%
Statutory Tax Rate			17.00%

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 8,347,000	$ 8,107,000	$ 24,957,000	$ 24,460,000
Stock Options Outstanding Roll Forward [Line Items]
Options outstanding at beginning of period			3,280
Options granted			115	32
Options exercised			(342)
Options canceled			(72)
Options outstanding at end of period	2,981		2,981
Weighted-average exercise price of options outstanding at beginning of period			$ 82.85
Weighted-average exercise price of options granted			121.33	$ 99.22
Weighted-average exercise price of options exercised			74.44
Weighted average exercise price of options canceled			83.25
Weighted-average exercise price of options outstanding at end of period	$ 85.29		$ 85.29
Stock Option Fair Value Assumptions and Methodology [Abstract]
Stock option fair value assumptions, risk free interest rate			1.40%	1.90%
Stock option fair value assumptions, expected life in years			4 years	4 years
Stock option fair value assumptions, expected volatility			29.10%	24.50%
Stock option fair value assumptions, expected dividends			$ 0	$ 0
Weighted-average grant date fair value of options granted			$ 30.85	$ 22.38
Restricted Stock Plan [Member]
Stock-Based Compensation by Award [Line Items]
Shares granted			10
Weighted-average grant date fair value of shares granted			$ 113.88
Restricted Stock Unit Plan [Member]
Stock-Based Compensation by Award [Line Items]
Unvested shares at beginning of period			533
Shares granted			150
Shares vested			(144)
Shares forfeited			(12)
Unvested shares at end of period	527		527
Weighted-average grant date fair value of shares unvested at beginning of period			$ 94.38
Weighted-average grant date fair value of shares granted			119.46
Weighted-average grant date fair value of shares vested			85.40
Weighted-average grant date fair value of shares forfeited			99.75
Weighted-average grant date fair value of shares unvested at end of period	$ 103.85		$ 103.85
Award vesting period			5 years
Minimum
Stock Options Outstanding Roll Forward [Line Items]
Weighted-average exercise price of options outstanding at beginning of period			$ 37.84
Weighted-average exercise price of options granted			113.88
Weighted-average exercise price of options exercised			37.84
Weighted average exercise price of options canceled			79.05
Weighted-average exercise price of options outstanding at end of period	38.09		38.09
Maximum
Stock Options Outstanding Roll Forward [Line Items]
Weighted-average exercise price of options outstanding at beginning of period			113.36
Weighted-average exercise price of options granted			134.37
Weighted-average exercise price of options exercised			98.21
Weighted average exercise price of options canceled			87.06
Weighted-average exercise price of options outstanding at end of period	$ 134.37		$ 134.37
Cost of sales [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 668,000	633,000	$ 1,990,000	$ 2,061,000
Selling and administrative expenses [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	6,626,000	6,355,000	19,686,000	19,345,000
Research and development expenses [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 1,053,000	$ 1,119,000	$ 3,281,000	$ 3,054,000

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	600	500	700	500
Earnings Per Share Reconciliation [Abstract]
Net income	$ 116,281	$ 113,497	$ 317,999	$ 280,328
Net income per basic common share	$ 1.42	$ 1.36	$ 3.85	$ 3.32
Effect of dilutive stock option, restricted stock and restricted stock unit securities	(0.02)	(0.02)	(0.03)	(0.03)
Net income per diluted common share	$ 1.40	$ 1.34	$ 3.82	$ 3.29
Weighted-average number of basic common shares	82,036	83,663	82,552	84,375
Effect of dilutive stock option, restricted stock and restricted stock unit securities on shares outstanding	748	738	753	787
Weighted-average number of diluted common shares and equivalents	82,784	84,401	83,305	85,162

Retirement Plans (Details)

Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Minimum
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions to defined benefit plans in current fiscal year			$ 6,000
Maximum
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions to defined benefit plans in current fiscal year			11,000
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,570	$ 1,623	4,596	$ 4,813
Expected return on plan assets	(2,223)	(2,179)	(6,859)	(6,795)
Net amortization: Net actuarial loss (gain)	1,101	692	2,459	1,662
Net periodic pension (benefit) cost	448	136	196	(320)
Defined benefit plan, contributions by employer			4,000
U.S. Retiree Healthcare Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	(91)	196	433	594
Interest cost	116	111	352	347
Expected return on plan assets	(129)	(112)	(373)	(326)
Net amortization: Prior service cost (credit)		(13)		(39)
Net amortization: Net actuarial loss (gain)		(18)		(26)
Net periodic pension (benefit) cost	(104)	164	412	550
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	1,337	1,212	4,011	3,636
Interest cost	402	592	1,206	1,776
Expected return on plan assets	(410)	(392)	(1,230)	(1,176)
Net amortization: Prior service cost (credit)	14	(47)	42	(141)
Net amortization: Net actuarial loss (gain)	273	97	819	291
Net periodic pension (benefit) cost	$ 1,616	$ 1,462	$ 4,848	$ 4,386

Business Segment Information (D

Business Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2015USD ($)	Sep. 27, 2014USD ($)	Oct. 03, 2015USD ($)	Sep. 27, 2014USD ($)
Entity-Wide Revenue from External Customers [Line Items]
Number of operating segments			2
Number of reportable segments			1
Product sales	$ 336,933	$ 331,165	$ 971,842	$ 937,225
Service sales	163,645	162,000	483,880	468,249
Total net sales	500,578	493,165	1,455,722	1,405,474
Waters instrument systems [Member]
Entity-Wide Revenue from External Customers [Line Items]
Product sales	219,196	213,122	625,276	595,670
Chemistry [Member]
Entity-Wide Revenue from External Customers [Line Items]
Product sales	78,173	77,853	234,095	229,633
TA instrument systems [Member]
Entity-Wide Revenue from External Customers [Line Items]
Product sales	39,564	40,190	112,471	111,922
Waters service [Member]
Entity-Wide Revenue from External Customers [Line Items]
Service sales	148,206	146,038	438,104	423,155
TA service [Member]
Entity-Wide Revenue from External Customers [Line Items]
Service sales	$ 15,439	$ 15,962	$ 45,776	$ 45,094