Waters (WAT) 10-Q 5 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	3 Months Ended
	Apr. 01, 2017	Apr. 28, 2017	Jul. 02, 2016
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	Q1
Document Period End Date	Apr. 1, 2017
Amendment Flag	false
Document Fiscal Year Focus	2,017
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			$ 11,522,067,374
Entity Common Stock, Shares Outstanding		80,037,534

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 584,444	$ 505,631
Investments	2,382,019	2,307,401
Accounts receivable, less allowances for doubtful accounts and sales returns of $8,046 and $8,657 at April 1, 2017 and December 31, 2016, respectively	461,755	489,340
Inventories	279,976	262,682
Other current assets	70,230	70,391
Total current assets	3,778,424	3,635,445
Property, plant and equipment, net	334,382	337,118
Intangible assets, net	211,049	207,055
Goodwill	353,796	352,080
Other assets	133,052	130,361
Total assets	4,810,703	4,662,059
Current liabilities:
Notes payable and debt	225,285	125,297
Accounts payable	66,929	67,740
Accrued employee compensation	29,872	57,465
Deferred revenue and customer advances	201,979	148,837
Accrued income taxes	2,892	15,244
Accrued warranty	12,998	13,391
Other current liabilities	92,256	92,347
Total current liabilities	632,211	520,321
Long-term liabilities:
Long-term debt	1,642,099	1,701,966
Long-term portion of retirement benefits	72,565	72,568
Long-term income tax liabilities	9,782	10,458
Other long-term liabilities	59,232	54,797
Total long-term liabilities	1,783,678	1,839,789
Total liabilities	2,415,889	2,360,110
Commitments and contingencies (Notes 5, 6 and 10)
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000 shares authorized, none issued at April 1, 2017 and December 31, 2016	0	0
Common stock, par value $0.01 per share, 400,000 shares authorized, 159,196 and 158,634 shares issued, 80,001 and 80,023 shares outstanding at April 1, 2017 and December 31, 2016, respectively	1,592	1,586
Additional paid-in capital	1,653,973	1,607,241
Retained earnings	5,490,626	5,385,069
Treasury stock, at cost, 79,195 and 78,611 shares at April 1, 2017 and December 31, 2016, respectively	(4,564,840)	(4,475,667)
Accumulated other comprehensive loss	(186,537)	(216,280)
Total stockholders' equity	2,394,814	2,301,949
Total liabilities and stockholders' equity	$ 4,810,703	$ 4,662,059

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Apr. 01, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
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	159,196,000	158,634,000
Common stock, shares outstanding	80,001,000	80,023,000
Treasury stock, shares	79,195,000	78,611,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Income Statement [Abstract]
Product sales	$ 324,296	$ 307,857
Service sales	173,673	167,389
Total net sales	497,969	475,246
Cost of product sales	133,156	129,258
Cost of service sales	77,939	71,893
Selling and administrative expenses	130,524	129,351
Research and development expenses	30,752	29,438
Purchased intangibles amortization	1,729	2,644
Acquired in-process research and development	5,000
Total costs and operating expenses	379,100	362,584
Operating income	118,869	112,662
Interest expense	(12,725)	(10,119)
Interest income	7,343	4,087
Income from operations before income taxes	113,487	106,630
Provision for income taxes	7,930	12,578
Net income	$ 105,557	$ 94,052
Net income per basic common share	$ 1.32	$ 1.16
Weighted-average number of basic common shares	80,073	81,275
Net income per diluted common share	$ 1.31	$ 1.15
Weighted-average number of diluted common shares and equivalents	80,769	81,974

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 105,557	$ 94,052
Foreign currency translation	29,141	16,051
Unrealized gains on investments before income taxes	588	3,289
Income tax expense from unrealized gains on investments	(22)	(93)
Unrealized gains on investments, net of tax	566	3,196
Retirement liability adjustment before reclassifications	(456)	(1,000)
Retirement liability amounts reclassified to selling and administrative expenses	836	810
Retirement liability adjustment before income taxes	380	(190)
Income tax expense from retirement liability adjustment	(344)	(278)
Retirement liability adjustment, net of tax	36	(468)
Other comprehensive income	29,743	18,779
Comprehensive income	$ 135,300	$ 112,831

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Cash flows from operating activities:
Net income	$ 105,557	$ 94,052
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	8,655	15,841
Deferred income taxes	6,168	3,740
Depreciation	12,783	12,356
Amortization of intangibles	10,167	11,075
Excess tax benefit related to stock-based compensation plans		1,619
In-process research and development charge	5,000
Change in operating assets and liabilities:
Decrease in accounts receivable	35,110	38,254
Increase in inventories	(10,473)	(20,488)
(Increase) decrease in other current assets	(4,057)	1,037
Increase in other assets	(1,040)	(3,421)
Decrease in accounts payable and other current liabilities	(50,072)	(43,632)
Increase in deferred revenue and customer advances	50,616	45,586
(Decrease) increase in other liabilities	5,795	5,486
Net cash provided by operating activities	174,209	161,505
Cash flows from investing activities:
Additions to property, plant, equipment and software capitalization	(17,711)	(24,652)
Investment in unaffiliated company	(7,000)
Purchases of investments	(823,335)	(685,568)
Maturities and sales of investments	750,997	512,397
Net cash used in investing activities	(97,049)	(197,823)
Cash flows from financing activities:
Proceeds from debt issuances	40,000	110,177
Payments on debt	(12)	(60,000)
Proceeds from stock plans	38,259	8,191
Purchases of treasury shares	(89,173)	(95,489)
Payments for derivative contracts	(1,438)	(1,895)
Net cash used in financing activities	(12,364)	(39,016)
Effect of exchange rate changes on cash and cash equivalents	14,017	4,056
Increase (decrease) in cash and cash equivalents	78,813	(71,278)
Cash and cash equivalents at beginning of period	505,631	487,665
Cash and cash equivalents at end of period	$ 584,444	$ 416,387

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Apr. 01, 2017
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 ( the “Company”) is a specialty measurement company that has pioneered chromatography, mass spectrometry and thermal analysis innovations serving the life, materials and food sciences for nearly 60 years. The Company primarily designs, manufactures, sells a nd services 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 quantif ication. In addition, t he Company designs, manufactures, sells and services thermal analysis, rheometry and calorimetry instruments through its TA ® product line. These instruments 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 supplier s ' 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 first fiscal quarters for 2017 and 2016 ended on April 1, 2017 and April 2, 2016 , 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, which are wholly owned. All 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, 2016 , as filed with the U.S. Securities and Exchange Commission on February 24, 2017. Translation of Foreign Currencies For most of the Company ' s foreign operations, assets and liabilities are translated into U.S. dollars at exchange rates prevailing on the balance sheet date, while revenues and expenses are translated at average exchange rates prevailing during the period . Any resulting translation gains or losses are included in accumulated other comprehensive income in the consolidated balance sheets . The functional currency of each of the Company ' s foreign operating subsidiaries is the loca l currency of that particular country, except for the Company ' s subsidiaries in Hong Kong , Singapore and the Cayman Islands, where the underlying transactional cash flows are denominated in currencies other tha n the respective local currency of domicile. The functional currency of the Hong Kong , Singapore and Cayman Islands subsidiaries is the U.S. dollar, based on the respective entity ' s cash flows. 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 the U.S. dollar. As of April 1, 2017 and December 31, 2016 , $2,929 million out of $2,966 million and $2,766 million out of $2,813 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. In addition, $295 million out of $2,966 million and $261 million out of $2,813 million of cash, cash equivalents and investments were held in currencies other than the U.S. dollar at April 1, 2017 and December 31, 2016 , respectively . Other Investments During the three months ended April 1, 2017 , the Company made a $7 million investment in a developer of analytical system solutions used to make measure ments , predict stability and accelerate product discovery in the routine ana lytic, process monitoring and quality control release processes for life science and biopharmaceutical mar kets. This investment will be accounted for u nder the cost method of accounting . 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 April 1, 2017 and December 31, 2016 . 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 that are measured at fair value on a recurring basis at April 1, 2017 (in thousands) : Quoted Prices in Active Significant Markets Other Significant for Identical Observable Unobservable Total at Assets Inputs Inputs April 1, 2017 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 522,012 $ - $ 522,012 $ - Foreign government securities 3,981 - 3,981 - Corporate debt securities 1,769,436 - 1,769,436 - Time deposits 305,462 - 305,462 - Equity securities 147 - 147 - Waters 401(k) Restoration Plan assets 32,894 32,894 - - Foreign currency exchange contracts 183 - 183 - Total $ 2,634,115 $ 32,894 $ 2,601,221 $ - Liabilities: Contingent consideration $ 3,010 $ - $ - $ 3,010 Foreign currency exchange contracts 985 - 985 - Total $ 3,995 $ - $ 985 $ 3,010 The following table represents the Company's assets and liabilities that are measured at fair value on a recu rring basis at December 31, 2016 (in thousands): Quoted Prices in Active Significant Markets Other Significant Total at for Identical Observable Unobservable December 31, Assets Inputs Inputs 2016 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 570,313 $ - $ 570,313 $ - Foreign government securities 17,991 - 17,991 - Corporate debt securities 1,643,838 - 1,643,838 - Time deposits 199,906 - 199,906 - Equity securities 147 - 147 - Waters 401(k) Restoration Plan assets 30,954 30,954 - - Foreign currency exchange contracts 60 - 60 - Total $ 2,463,209 $ 30,954 $ 2,432,255 $ - Liabilities: Contingent consideration $ 3,007 $ - $ - $ 3,007 Foreign currency exchange contracts 730 - 730 - Total $ 3,737 $ - $ 730 $ 3,007 Fair Value of 401(k) Restoration Plan Assets The 401(k) Restoration Plan is a nonqualified defined contribution plan and the assets were h eld in registered mutual funds and have been classified as Level 1 . The fair values of the assets in this plan are determined through market and observable sources from daily quoted prices on nationally recognized securities exchanges. Fair Value of Cash Equivalents, Investment and Foreign Currency Exchange Contracts T he fair values of the Company's cash equivalents, investments 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 April 1, 2017 and December 31, 2016 . There were no transfers between the levels of the fair value hierarchy during the three months ended April 1, 2017 . Fair Value of Contingent Consideration The fair value of the Company' s liability for contingent consideration relates to the July 2014 acquisition of Medimass Research, Development and Service Kft . and 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 estimated future results and a discount rate that reflects both the likelihood of achieving the estimated future results and the Company ' s creditworthiness . A change in any of these unobservable inputs can significantly change the fair value of the contingent consideration. Although ther e is no contractual limit, the fair value of future contin gent consideration payments was estimated to be $3 million at both April 1, 2017 and December 31, 2016 , based on the Company ' s best estimate, as the earnout is based on future sales of certain products , some of which are currently in development, through 2034. There have been no changes in significant assumptions since December 31, 2016 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 due to their short-term nature . The carrying value of the Company's fixed interest rate debt was $610 million at both April 1, 2017 and December 31, 2016 . 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 $608 million and $603 million at April 1, 2017 and December 31, 2016 , respectively , using Level 2 inputs. Derivative Transactions The Company is a global company that operates i n over 35 countries and, as a result, the Company's net sales, cost of sales, operating expenses and balance sheet amounts are significantly impacted by fluctuations in foreign currency exchange rates. The Company is exposed to currency price risk on foreign currency exchange rate fluctuations when it translates its non-U.S. dollar foreign subsidiaries' financial statements into U.S. dollars, and when any of the Company's subsidiaries purchase or sell products or services in a currency other than its own currency. The Company's principal strategy in managing exposure to changes in foreign currency exchange rates is to naturally hedge the foreign-currency-denominated liabilities on the Company's balance sheet against corresponding assets of the same currency, such that any changes in liabilities due to fluctuations in foreign currency exchange rates are typically offset by corresponding changes in assets. The Company does not specifically enter into any derivatives that hedge foreign - currency - denominated assets, liabilities or commitments on its balance sheet, other than a portion of certain third-party accounts receivable and accounts payable, and the Company's net worldwide intercompany receivables and payables, which are eliminated in consolidation. The Company periodically aggregates its net worldwide balances by currency and then enters into foreign currency exchange contracts that mature within 90 days to hedge a portion of the remaining balance to minimize some of the Company's currency price risk exposure. The foreign currency exchange contracts are not designated for hedge accounting treatment. Principal hedged currenc ies include the Euro, Japanese y en, Britis h pound , Mexican peso and Brazilian real . At April 1, 2017 and December 31, 2016 , the Company held foreign currency exchange contracts with notional amounts totaling $124 million and $120 million, respectively. T he Company's foreign currency exchange contracts included in the consolid ated balance sheets are classified as follows (in thousands): April 1, 2017 December 31, 2016 Other current assets $ 183 $ 60 Other current liabilities $ 985 $ 730 The following is a summary of the activity included in cost of sales in the statements of operations related to the foreign currency exchange contracts (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Realized losses on closed contracts $ (1,438) $ (1,895) Unrealized losses on open contracts (132) (28) Cumulative net pre-tax losses $ (1,570) $ (1,923) 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 . During the three months ended April 1, 2017 and April 2, 2016 , t he Company repurchased 0.5 million and 0.7 million shares of the Company's outstanding common stock at a cost of $ 82 million and $ 89 million , respectively, under the May 2014 authorization . The Company has a total of $41 million authorized for future repurchases under the May 2014 plan . In addition, the Company repurchased $7 million and $6 million of common stock related to the vesting of restricted stock units during the three months ended April 1, 2017 and April 2, 2016 , 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 three months ended April 1, 2017 and April 2, 2016 (in thousands): Balance at Balance at Beginning Accruals for Settlements End of of Period Warranties Made Period Accrued warranty liability: April 1, 2017 $ 13,391 $ 1,815 $ (2,208) $ 12,998 April 2, 2016 $ 13,349 $ 1,681 $ (2,198) $ 12,832 Restructuring and Other Charge s During the three months ended April 1, 2017 , the Company incurred $9 million of severance costs associated with the closure of a facility in Germany and costs associated with providing U.S. employees with an early retirement transition incentive. During the three months ended April 2, 2016 , the Company incurred $3 million of severance costs associated with an organizational restructuring. At April 1, 2017 , the Company had $6 million of severance costs accrued in other current liabilities. Acquired In-process Research and Development During the three months ended April 1, 2017 , the Company incurred a $5 million charge for acquired in-process research and development related to a milestone payment for the licensing of certa in intellectual property relating to mass spectrometry technologies yet to be commercialized and for which there was no future alternative use as of the acquisition date. Thi s licensing arrangement is significantly related to new, biologically-focused applications, as well as other applications, and require the Company to make additional future payments of up to $7 million if certain milestones are achieved, as well as royalties on future net sales.

Marketable Securities

Marketable Securities	3 Months Ended
	Apr. 01, 2017
Marketable Securities [Abstract]
Marketable Securities	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): April 1, 2017 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 522,628 $ 96 $ (712) $ 522,012 Foreign government securities 3,981 - - 3,981 Corporate debt securities 1,770,252 916 (1,732) 1,769,436 Time deposits 305,462 - - 305,462 Equity securities 77 70 - 147 Total $ 2,602,400 $ 1,082 $ (2,444) $ 2,601,038 Amounts included in: Cash equivalents $ 219,022 $ - $ (3) $ 219,019 Investments 2,383,378 1,082 (2,441) 2,382,019 Total $ 2,602,400 $ 1,082 $ (2,444) $ 2,601,038 December 31, 2016 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 570,695 $ 253 $ (635) $ 570,313 Foreign government securities 17,999 - (8) 17,991 Corporate debt securities 1,645,468 496 (2,126) 1,643,838 Time deposits 199,906 - - 199,906 Equity securities 77 70 - 147 Total $ 2,434,145 $ 819 $ (2,769) $ 2,432,195 Amounts included in: Cash equivalents $ 124,793 $ 1 $ - $ 124,794 Investments 2,309,352 818 (2,769) 2,307,401 Total $ 2,434,145 $ 819 $ (2,769) $ 2,432,195 The estimated fair value of marketable debt securities by maturity date is as follows (in thousands): April 1, 2017 December 31, 2016 Due in one year or less $ 1,456,067 $ 1,388,537 Due after one year through three years 839,362 843,605 Total $ 2,295,429 $ 2,232,142

Inventories

Inventories	3 Months Ended
	Apr. 01, 2017
Inventory Items, Net Of Reserves Alternative [Abstract]
Inventories Disclosure	3 Inventories Inventories are classi fied as follows (in thousands): April 1, 2017 December 31, 2016 Raw materials $ 91,981 $ 95,430 Work in progress 17,598 16,585 Finished goods 170,397 150,667 Total inventories $ 279,976 $ 262,682

Goodwill and Other Intangibles

Goodwill and Other Intangibles	3 Months Ended
	Apr. 01, 2017
Goodwill and Other Intangibles [Abstract]
Goodwill and Other Intangibles	4 Goodwill and Other Intangibles The carrying amount of goodwill was $ 354 million and $ 352 million at April 1, 2017 and December 31, 2016 , respectively . During the three months ended April 1, 2017 , the effect of foreign currency translation in creased goodwill by $ 2 million. T he Company's intangible assets included in the consolidated balance sheets are detailed as follows (in thousands): April 1, 2017 December 31, 2016 Weighted- Weighted- Gross Average Gross Average Carrying Accumulated Amortization Carrying Accumulated Amortization Amount Amortization Period Amount Amortization Period Capitalized software $ 372,247 $ 235,359 5 years $ 355,973 $ 223,572 5 years Purchased intangibles 163,667 129,710 11 years 162,180 127,045 11 years Trademarks and IPR&D 13,623 - - 13,544 - - Licenses 5,218 4,017 6 years 4,632 3,851 6 years Patents and other intangibles 63,367 37,987 8 years 61,646 36,452 8 years Total $ 618,122 $ 407,073 7 years $ 597,975 $ 390,920 7 years During the three months ended April 1, 2017 , the effect of foreign currency translation increase d the gross carrying value of intangible assets and accumulated amortization for intangible assets by $10 million and $6 million, respectively. A mortization expe nse fo r intangible assets was $10 million and $11 million f or the three months ended April 1, 2017 and April 2, 2016 , respectively . A mortization expense for intangible assets is estimated to be approximately $ 43 million per year for each of the next five years.

Debt

Debt	3 Months Ended
	Apr. 01, 2017
Debt [Abstract]
Debt Disclosure	5 Debt In June 2013, the Company entered into a credit agreement that provides for a $1.1 billion revolving facility and a $300 million term loan facility. In April 2015, Waters Corporation entered into an amendment to this agreement (the “Amended Credit Agreement”). The Amended Credit Agreement 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 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 basis points 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. The facility fee on the Amended Credit Agreement ranges between 7.5 basis points and 20 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 3.50:1 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. At April 1, 2017 , $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 $745 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. T he Company had a total of $700 million of outstanding senior unsecured notes as of April 1, 2017 and December 31, 2016 . 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 and J 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 April 1, 2017 and December 31, 2016 (in thousands) : April 1, 2017 December 31, 2016 Foreign subsidiary lines of credit $ 285 $ 297 Senior unsecured notes - Series D - 3.22%, due March 2018 100,000 - Credit agreements 125,000 125,000 Total notes payable and debt 225,285 125,297 Senior unsecured notes - Series B - 5.00%, due February 2020 100,000 100,000 Senior unsecured notes - Series D - 3.22%, due March 2018 - 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 Senior unsecured notes - Series I - 3.13%, due May 2023 50,000 50,000 Senior unsecured notes - Series J - floating rate**, due May 2024 40,000 40,000 Senior unsecured notes - Series K - 3.44%, due May 2026 160,000 160,000 Credit agreements 1,045,000 1,005,000 Unamortized debt issuance costs (2,901) (3,034) Total long-term debt 1,642,099 1,701,966 Total debt $ 1,867,384 $ 1,827,263 * Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%. ** Series J senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.45%. As of April 1, 2017 and December 31, 2016 , the Company had a total amount available to borrow under existing credit agreements of $ 428 million and $ 468 million, respectively, after outstanding letters of credit . T he weighted-average interest rates applicable to the senior unsecured notes and c redit a greement borrowings collectively were 2.68% and 2.55% at April 1, 2017 and December 31, 2016 , respectively. As of April 1, 2017 , the Company was in compliance with all debt covenants. The Company and its foreign subsidiaries also had available short-term lines of credit totaling $81 million and $ 79 million at April 1, 2017 and December 31, 2016 , respectively, for the purpose of short-term borrowing and issuance of commercial guarantees. At April 1, 2017 and December 31, 2016 , t he weighted-average interest rates applicable to these short-term borrowings were 1.48% and 1.49% , respectively.

Income Taxes

Income Taxes	3 Months Ended
	Apr. 01, 2017
Income Taxes [Abstract]
Income Taxes	6 Income Taxes The four principal jurisdictions in which the Company manufactures are the U.S., Ireland, the U.K. and Singapore, where the Company's marginal effective tax rates we re approximately 37.5%, 12.5%, 19.25 % and 0%, respectively, as of April 1, 2017 . The Company has a contractual tax rate of 0% on qualifying activities in Singapore through March 2021, based upon the achievement of certain contractual milestones, which the Company expects to continue to meet. The current statutory tax rate in Singapore is 17%. For the first quarter of 2017 and 2016, the effect of applying the contractual tax rate rather than the statutory tax rate to income from qualifying activities in Singapore increase d the Company's net income by $5 million and $4 million, respectively, and increased the Company's net i ncome per diluted share by $0.06 and $0.05, respectively. The Company's effective tax rate for the quarter was 7.0% and 11.8% for 2017 and 2016, respectively. The decrease in the effective tax rate in 2017 as compared to 2016 can be primarily attributed to the adoption of new accounting guidance related to stock -based compensation , which decreased income tax expense by $7 million and decreased the Company's effective tax rate by 6.3 percentage points in the first quarter of 2017 . S ee Note 12 for further information regarding the adoption of this standard . In addition, the provision for income taxes for the first quarter of 2016 included a quarter-specific tax benefit associated with modifications to certain stock -based compensation awards. The remaining differences between the effective tax rate in 2017 and 2016 can be primarily attributed to differences in the proportionate amounts of pre-tax income recognized in jurisdictions with different effective tax rates. 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 tax 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 Company classified interest and penalties related to unrecognized tax benefits as a component of the provision for income taxes . The following is a summary of the activity of the Company's unrecognized tax benefits for the three months ended April 1, 2017 and April 2, 2016 (in thousands): April 1, 2017 April 2, 2016 Balance at the beginning of the period $ 9,964 $ 14,450 Net changes in uncertain tax benefits (717) (790) Balance at the end of the period $ 9,247 $ 13,660 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 1 2 . However, carryforward tax attributes that were generated in years beginning on or before January 1, 201 3 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 April 1, 2017 , the Company expects to record additional reductions in the measurement of its unrecognized tax benefits and related net interest and penalties of approximately $ 4 million within the next twelve months due to potential tax audit settlements and 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	3 Months Ended
	Apr. 01, 2017
Stock-Based Compensation [Abstract]
Stock-Based Compensation	7 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 and performance stock units ). In the first quarter of 2017, the Company adopted new accounting guidance related to stock -based compensation, see Note 12 for further information regarding the adoption of this standard. 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 new stock-based compensation accounting guidance offers the option of recognizing forfeitures as they occur or estimat ing forfeitures at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company has elected to remain consistent with prior periods and estimate forfeitures at the time of grant and, if necessary, revise in subsequent periods in which actual forfeitures differ from those estimates. Forfeitures are 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 months ended April 1, 2017 and April 2, 2016 include the following stock-based compensation expense related to stock option awards, restricted stock awards , restricted stock unit awards, performance stock unit awards and the employee stock purchase plan (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Cost of sales $ 738 $ 671 Selling and administrative expenses 7,188 13,969 Research and development expenses 729 1,201 Total stock-based compensation $ 8,655 $ 15,841 During the three months ended April 2, 2016 , the Company recognized $7 million of stock -based compensation expense related to the modification of certain stock awards upon the retirement of senior executive s . 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 three months ended April 1, 2017 and April 2, 2016 are as follows: Options Issued and Significant Assumptions Used to Estimate Option Fair Values April 1, 2017 April 2, 2016 Options issued in thousands 207 86 Risk-free interest rate 2.2% 1.5% Expected life in years 6 5 Expected volatility 0.232 0.286 Expected dividends - - Weighted-Average Exercise Price and Fair Value of Options on the Date of Grant April 1, 2017 April 2, 2016 Exercise price $ 149.74 $ 122.65 Fair value $ 40.39 $ 34.63 T he following table summarizes stock option activity for the plans for the three months ended April 1, 2017 (in thousands, except per share data): Number of Shares Price per Share Weighted-Average Exercise Price Outstanding at December 31, 2016 2,697 $ 38.09 to $ 139.51 $ 106.55 Granted 207 $ 136.43 to $ 154.33 $ 149.74 Exercised (415) $ 41.20 to $ 128.93 $ 89.05 Canceled (43) $ 87.06 to $ 136.43 $ 113.05 Outstanding at April 1, 2017 2,446 $ 38.09 to $ 154.33 $ 113.06 Restricted Stock During the three months ended April 1, 2017 , the Company granted seven thousand shares of restricted stock. The weighted-average fair value per share of these awards on the grant date was $ 136.43 per share . Restricted Stock Units The following table summarizes the unvested restricted stock unit award activity for the three months ended April 1, 2017 (in thousands, except for per share data ): Shares Weighted-Average Price Unvested at December 31, 2016 453 $ 110.34 Granted 105 $ 154.08 Vested (131) $ 105.13 Forfeited (11) $ 111.50 Unvested at April 1, 2017 416 $ 122.99 Restricted stock units are generally granted annually in February and vest in equal annual insta llments over a five-year period. Performance Stock Units During three months ended April 1, 2017 , the Company issued performance stock units, which are equity compensation awards with a market vesting condition based on the Company's Total Shareholder Return (“TSR”) relative to the TSR of the components of the S&P Health Care Index. TSR is the change in value of a stock price over time, including the reinvestment of dividends. The vesting schedule ranges from 0% to 200% of the target shares awarded. In determining the fair value of the performance stock units, the Company makes a variety of assumptions and estimates, including volatility measures, expected yields and expected terms. The fair value of each performance stock unit grant was estimated on the date of grant using the Monte Carlo simulation 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 the performance period of the underlying performance stock units. 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 Monte Carlo simulation model. The correlation coefficient is used to model the way in which each company in the S&P Health Care Index tends to move in relation to each other during the performance period. The relevant data used to determine the value of the performance stock u nits granted during 2017 is as follows: Performance Stock Units Issued and Significant Assumptions Used to Estimate Fair Values 2017 Performance stock units issued in thousands 20 Risk-free interest rate 1.5% Expected life in years 3 Expected volatility 0.232 Average volatility of peer companies 0.261 Correlation coefficient 0.385 Expected dividends - The following table summarizes the unvested performance stock unit a ward activity for the three months ended April 1, 2017 (in thousands, except for per share data ): Shares Weighted-Average Fair Value Unvested at December 31, 2016 27 $ 171.16 Granted 20 $ 198.78 Unvested at April 1, 2017 47 $ 184.40

Earnings Per Share

Earnings Per Share	3 Months Ended
	Apr. 01, 2017
Earnings Per Share [Abstract]
Earnings Per Share	8 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 April 1, 2017 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 105,557 80,073 $ 1.32 Effect of dilutive stock option, restricted stock, performance stock unit and restricted stock unit securities - 696 (0.01) Net income per diluted common share $ 105,557 80,769 $ 1.31 Three Months Ended April 2, 2016 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 94,052 81,275 $ 1.16 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 699 (0.01) Net income per diluted common share $ 94,052 81,974 $ 1.15 For t he three months ended April 1, 2017 and April 2, 2016 , the Company had 1.1 million and 1.2 million stock options that were antidilutive , respectively, due to having higher exercise prices than the Company's average stock price during the period. These securities were not included in the computation of diluted EPS. The effect of dilutive securities was calculated using the treasury stock method.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Apr. 01, 2017
Equity [Abstract]
Accumulated Other Comprehensive Income	9 Accumulated Other Comprehensive Income The components of accumulated other comprehensive income are detailed as follows (in th ousands ): Currency Translation Unrealized Gain (Loss) on Retirement Plans Unrealized Gain (Loss) on Investments Accumulated Other Comprehensive Income (Loss) Balance at December 31, 2016 $ (170,566) $ (43,894) $ (1,820) $ (216,280) Other comprehensive income, net of tax 29,141 36 566 29,743 Balance at April 1, 2017 $ (141,425) $ (43,858) $ (1,254) $ (186,537)

Retirement Plans

Retirement Plans	3 Months Ended
	Apr. 01, 2017
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 months ended April 1, 2017 and April 2, 2016 is as follows (in thousands): Three Months Ended April 1, 2017 April 2, 2016 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 $ 101 $ 103 $ 1,251 $ 94 $ 116 $ 1,218 Interest cost 1,719 150 358 1,745 135 421 Expected return on plan assets (2,663) (147) (402) (2,417) (130) (399) Net amortization: Prior service credit - - (46) - - (45) Net actuarial loss 651 - 231 667 - 188 Net periodic pension (benefit) cost $ (192) $ 106 $ 1,392 $ 89 $ 121 $ 1,383 During fiscal year 2017 , 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	3 Months Ended
	Apr. 01, 2017
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 ® and TA . The Waters operating segment 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. The TA operating segment is primarily in the business of designing, manufacturing, distributing and servicing thermal analysis, rheometry and calorimetry instruments. The Company's two operating segments ha ve 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 months ended April 1, 2017 and April 2, 2016 (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Product net sales: Waters instrument systems $ 197,789 $ 188,529 Chemistry 87,903 84,150 TA instrument systems 38,604 35,178 Total product sales 324,296 307,857 Service net sales: Waters service 157,734 151,514 TA service 15,939 15,875 Total service sales 173,673 167,389 Total net sales $ 497,969 $ 475,246

Recent Accounting Standard Chan

Recent Accounting Standard Changes and Developments	3 Months Ended
	Apr. 01, 2017
Recent Accounting Standard Changes and Developments [Abstract]
Recent Accounting Standard Changes and Developments	12 Recent Accounting Standard Changes and Developments Recently Adopted Accounting Standards In July 2015, accounting guidance was issued which clarifies the measurement of inventory. The new guidance requires inventory to be m easured 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 beginning after December 15, 2016. The Company adopted this standard as of January 1, 2017 and this standard did not have a material effect on the Company ' s financial position, results of operations and cash flows. In March 2016, accounting guidance was issued which simplifies the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statemen t of cash flows. This guidance is effective for annual and interim reporting periods beginning after December 15, 2016. The new guidance is required to be adopted on a prospective basis for the statement of operations and the Company has elected to retrospectively apply the cash flow aspects of this new guidance. In addition, the Company has elected to continue to estimate forfeitures at the time of grant and update forfeiture estimates throughout the requisite service period. The Company adopted this standard as of January 1, 2017 and recognized a n excess tax benefit related to stock -based compensation in the first quarter of 2017 , which decreased income tax expense by $7 million and added $ 0.09 to net income per diluted share. These excess tax benefits were previously recorded in equity and there were no cumulative-effect adjustments to retained earnings as a result of the adoption of this standard. In addition, the Company reclassified $2 million of ex cess tax benefits related to stock -based compensation for the first quarter of 2016 from cash flows from financing activities to cash flows from operating activities. 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 (“FASB”) amended the standard in August 2015 to delay the effective period date by one year to annual and interim periods beginning after December 15, 2017. Adoption prior to December 15, 2016 is not permitted. In March 2016, the FASB clarified the implementation guidance on principal versus agent considerations and, in April 2016, clarification was made regarding certain aspects of identifying performance obligations and licensing implementation guidance. In May 2016, additional guidance was issued related to disclosure of remaining performance obligations, as well as other amendments to guidance on collectibility, non-cash consideration and the presentation of sales and other similar taxes collected from customers. The Company does not intend to early adopt this accounting standard and will apply the modified-retrospective method. 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 January 2016, accounting guidance was issued which primarily affects the classification and measurement of certain financial instruments, principally equity investments and certain financial liabilities. Under the new guidance, there will no longer be an available-for-sale classification for equity securities with readily determinable fair values. Changes to the fair value of equity investments will be recognized through earnings. Equity investments carried at cost should be adjusted for changes in observable prices, as applicable, and qualitatively assessed for impairment annually. Changes to the fair value of financial liabilities under the fair value option due to instrument specific credit risk will be recognized separately in other comprehensive income. The new guidance also requires financial assets and financial liabilities to be presented separately and grouped by measurement category in the notes to the financial statements. This guidance is effective for annual and interim reporting periods beginning after December 15, 2017 and early adoption of certain provisions of this guidance is permitted. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows. In February 2016, accounting guidance was issued regarding the accounting for leases. This new comprehensive lease standard amends various aspects of existing accounting guidance for leases. The core principle of the new guidance will require lessees to present the assets and liabilities that arise from leases on their balance sheets. This guidance is effective for annual and interim reporting periods beginning after December 15, 2018 and early adoption is permitted. The Company expects that the adoption of this standard will have a material effect on the Company ' s balance sheet classifications; however, it is not expected to have an overall material impact on the Company ' s results of operations and cash flows. In June 2016, accounting guidance was issued that modifies the recognition of credit losses related to financial assets, such as debt securities, trade receivables, net investments in leases, off-balance sheet credit exposures, and other financial assets that have the contractual right to receive cash. Current guidance requires the recognition of a credit loss when it is considered probable that a loss event was incurred. The new guidance requires the measurement of expected credit losses to be based upon relevant information, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the asset. As such, expected credit losses may be recognized sooner under the new guidance due to the broader range of information that will be required to determine credit loss estimates. The new guidance also amends the current other-than-temporary impairment model used for debt securities classified as available-for-sale. When the fair value of an available-for-sale debt security is below its amortized cost, the new guidance requires the total unrealized loss to be bifurcated into its credit and non-credit components. Any expected credit losses or subsequent recoveries will be recognized in earnings and any changes not considered credit related will continue to be recognized within other comprehensive income. This guidance is effective for annual and interim periods beginning after December 15, 2019. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows. In August 2016, accounting guidance was issued that clarifies the classification of certain cash flows. The new guidance addresses eight specific areas where current accounting guidance is either unclear or does not specifically address classification issues. This guidance is effective for annual and interim periods beginning after December 15, 201 7 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 cash flows. In October 2016, accounting guidance was issued regarding intra-entity transfers of assets other than inventory. The new guidance eliminates the deferral of tax effects on intra-entity transfers other than inventory and requires an entity to recognize the income tax consequences when the transfer occurs. This guidance is effective for annual and interim periods beginning after December 15, 2017 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 January 2017, accounting guidance was issued that clarifies the definition of a business. The new guidance provides a more robust framework to use in determining when a set of assets and activities is a business, thus narrowing the definition and the amount of transactions accounted for as business combinations. This guidance is effective for annual and interim periods beginning after December 15, 2017 and early application is permitted under certain circumstances. 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 January 2017, accounting guidance was issued that simplifies the accounting for goodwill impairment. The guidance eliminates step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. This guidance is effective for annual and interim periods beginning after December 15, 2019 and early adoption is permitted. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows . I n March 2017, accounting guidance was issued regarding the presentation of net periodic pension cost and net periodic postretirement benefit cost. The new guidance requires that an employer disaggregate the service cost component from other components of net benefit cost, with service cost reported in the same line items as other compensation costs and the other components of net benefit costs presented outside income from operations . This guidance is effective for annual and interim periods beginning after December 15, 2017 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, resul ts of operations and cash flows . In March 2017, accounting guidance was issued to amend the amortization period for certain purchased callable debt securities held at a premium. Specifically, the amortization period for certain callable debt securities will be shortened to end at the earliest call date. This guidance is effective for annual and interim periods beginning after December 15, 201 8 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, resul ts of operations and cash flows .

Basis of Presentation and Sum19

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Apr. 01, 2017
Basis of Presentation and Summary of Significant Accounting Policies [Abstract]
Nature of Operations	Waters Corporation ( the “Company”) is a specialty measurement company that has pioneered chromatography, mass spectrometry and thermal analysis innovations serving the life, materials and food sciences for nearly 60 years. The Company primarily designs, manufactures, sells a nd services 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 quantif ication. In addition, t he Company designs, manufactures, sells and services thermal analysis, rheometry and calorimetry instruments through its TA ® product line. These instruments 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 supplier s ' instruments, and are typically purchased by customers as part of the instrument system.
Fiscal Period	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 first fiscal quarters for 2017 and 2016 ended on April 1, 2017 and April 2, 2016 , 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, 2016 , as filed with the U.S. Securities and Exchange Commission on February 24, 2017.
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.
Principles of Consolidation	The consolidated financial statements include the accounts of the Company and its subsidiaries, which are wholly owned. All inter-company balances and tra nsactions have been eliminated.
Translation of Foreign Currencies	Translation of Foreign Currencies For most of the Company ' s foreign operations, assets and liabilities are translated into U.S. dollars at exchange rates prevailing on the balance sheet date, while revenues and expenses are translated at average exchange rates prevailing during the period . Any resulting translation gains or losses are included in accumulated other comprehensive income in the consolidated balance sheets . The functional currency of each of the Company ' s foreign operating subsidiaries is the loca l currency of that particular country, except for the Company ' s subsidiaries in Hong Kong , Singapore and the Cayman Islands, where the underlying transactional cash flows are denominated in currencies other tha n the respective local currency of domicile. The functional currency of the Hong Kong , Singapore and Cayman Islands subsidiaries is the U.S. dollar, based on the respective entity ' s cash flows.
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 April 1, 2017 and December 31, 2016 . 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 due to their short-term nature .
Derivatives Policy	The foreign currency exchange contracts are not designated for hedge accounting treatment.
Product Warranty Costs	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.

Income Taxes (Policies)

Income Taxes (Policies)	3 Months Ended
	Apr. 01, 2017
Income Taxes [Abstract]
Income Tax 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 tax 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 Company classified interest and penalties related to unrecognized tax benefits as a component of the provision for income taxes .

Stock-Based Compensation (Polic

Stock-Based Compensation (Policies)	3 Months Ended
	Apr. 01, 2017
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 new stock-based compensation accounting guidance offers the option of recognizing forfeitures as they occur or estimat ing forfeitures at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company has elected to remain consistent with prior periods and estimate forfeitures at the time of grant and, if necessary, revise in subsequent periods in which actual forfeitures differ from those estimates. Forfeitures are 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. Performance Stock Units In determining the fair value of the performance stock units, the Company makes a variety of assumptions and estimates, including volatility measures, expected yields and expected terms. The fair value of each performance stock unit grant was estimated on the date of grant using the Monte Carlo simulation 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 the performance period of the underlying performance stock units. 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 Monte Carlo simulation model. The correlation coefficient is used to model the way in which each company in the S&P Health Care Index tends to move in relation to each other during the performance period.

Earnings Per Share (Policies)

Earnings Per Share (Policies)	3 Months Ended
	Apr. 01, 2017
Earnings Per Share [Abstract]
Earnings Per Share Policy	The effect of dilutive securities was calculated using the treasury stock method.

Recent Accounting Standard Ch23

Recent Accounting Standard Changes and Develpments (Policies)	3 Months Ended
	Apr. 01, 2017
Recent Accounting Standard Changes and Developments [Abstract]
New Accounting Pronouncements	12 Recent Accounting Standard Changes and Developments Recently Adopted Accounting Standards In July 2015, accounting guidance was issued which clarifies the measurement of inventory. The new guidance requires inventory to be m easured 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 beginning after December 15, 2016. The Company adopted this standard as of January 1, 2017 and this standard did not have a material effect on the Company ' s financial position, results of operations and cash flows. In March 2016, accounting guidance was issued which simplifies the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statemen t of cash flows. This guidance is effective for annual and interim reporting periods beginning after December 15, 2016. The new guidance is required to be adopted on a prospective basis for the statement of operations and the Company has elected to retrospectively apply the cash flow aspects of this new guidance. In addition, the Company has elected to continue to estimate forfeitures at the time of grant and update forfeiture estimates throughout the requisite service period. The Company adopted this standard as of January 1, 2017 and recognized a n excess tax benefit related to stock -based compensation in the first quarter of 2017 , which decreased income tax expense by $7 million and added $ 0.09 to net income per diluted share. These excess tax benefits were previously recorded in equity and there were no cumulative-effect adjustments to retained earnings as a result of the adoption of this standard. In addition, the Company reclassified $2 million of ex cess tax benefits related to stock -based compensation for the first quarter of 2016 from cash flows from financing activities to cash flows from operating activities. 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 (“FASB”) amended the standard in August 2015 to delay the effective period date by one year to annual and interim periods beginning after December 15, 2017. Adoption prior to December 15, 2016 is not permitted. In March 2016, the FASB clarified the implementation guidance on principal versus agent considerations and, in April 2016, clarification was made regarding certain aspects of identifying performance obligations and licensing implementation guidance. In May 2016, additional guidance was issued related to disclosure of remaining performance obligations, as well as other amendments to guidance on collectibility, non-cash consideration and the presentation of sales and other similar taxes collected from customers. The Company does not intend to early adopt this accounting standard and will apply the modified-retrospective method. 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 January 2016, accounting guidance was issued which primarily affects the classification and measurement of certain financial instruments, principally equity investments and certain financial liabilities. Under the new guidance, there will no longer be an available-for-sale classification for equity securities with readily determinable fair values. Changes to the fair value of equity investments will be recognized through earnings. Equity investments carried at cost should be adjusted for changes in observable prices, as applicable, and qualitatively assessed for impairment annually. Changes to the fair value of financial liabilities under the fair value option due to instrument specific credit risk will be recognized separately in other comprehensive income. The new guidance also requires financial assets and financial liabilities to be presented separately and grouped by measurement category in the notes to the financial statements. This guidance is effective for annual and interim reporting periods beginning after December 15, 2017 and early adoption of certain provisions of this guidance is permitted. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows. In February 2016, accounting guidance was issued regarding the accounting for leases. This new comprehensive lease standard amends various aspects of existing accounting guidance for leases. The core principle of the new guidance will require lessees to present the assets and liabilities that arise from leases on their balance sheets. This guidance is effective for annual and interim reporting periods beginning after December 15, 2018 and early adoption is permitted. The Company expects that the adoption of this standard will have a material effect on the Company ' s balance sheet classifications; however, it is not expected to have an overall material impact on the Company ' s results of operations and cash flows. In June 2016, accounting guidance was issued that modifies the recognition of credit losses related to financial assets, such as debt securities, trade receivables, net investments in leases, off-balance sheet credit exposures, and other financial assets that have the contractual right to receive cash. Current guidance requires the recognition of a credit loss when it is considered probable that a loss event was incurred. The new guidance requires the measurement of expected credit losses to be based upon relevant information, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the asset. As such, expected credit losses may be recognized sooner under the new guidance due to the broader range of information that will be required to determine credit loss estimates. The new guidance also amends the current other-than-temporary impairment model used for debt securities classified as available-for-sale. When the fair value of an available-for-sale debt security is below its amortized cost, the new guidance requires the total unrealized loss to be bifurcated into its credit and non-credit components. Any expected credit losses or subsequent recoveries will be recognized in earnings and any changes not considered credit related will continue to be recognized within other comprehensive income. This guidance is effective for annual and interim periods beginning after December 15, 2019. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows. In August 2016, accounting guidance was issued that clarifies the classification of certain cash flows. The new guidance addresses eight specific areas where current accounting guidance is either unclear or does not specifically address classification issues. This guidance is effective for annual and interim periods beginning after December 15, 201 7 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 cash flows. In October 2016, accounting guidance was issued regarding intra-entity transfers of assets other than inventory. The new guidance eliminates the deferral of tax effects on intra-entity transfers other than inventory and requires an entity to recognize the income tax consequences when the transfer occurs. This guidance is effective for annual and interim periods beginning after December 15, 2017 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 January 2017, accounting guidance was issued that clarifies the definition of a business. The new guidance provides a more robust framework to use in determining when a set of assets and activities is a business, thus narrowing the definition and the amount of transactions accounted for as business combinations. This guidance is effective for annual and interim periods beginning after December 15, 2017 and early application is permitted under certain circumstances. 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 January 2017, accounting guidance was issued that simplifies the accounting for goodwill impairment. The guidance eliminates step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. This guidance is effective for annual and interim periods beginning after December 15, 2019 and early adoption is permitted. The Company currently does not expect that the adoption of this standard will have a material effect on the Company ' s financial position, results of operations and cash flows . I n March 2017, accounting guidance was issued regarding the presentation of net periodic pension cost and net periodic postretirement benefit cost. The new guidance requires that an employer disaggregate the service cost component from other components of net benefit cost, with service cost reported in the same line items as other compensation costs and the other components of net benefit costs presented outside income from operations . This guidance is effective for annual and interim periods beginning after December 15, 2017 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, resul ts of operations and cash flows . In March 2017, accounting guidance was issued to amend the amortization period for certain purchased callable debt securities held at a premium. Specifically, the amortization period for certain callable debt securities will be shortened to end at the earliest call date. This guidance is effective for annual and interim periods beginning after December 15, 201 8 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, resul ts of operations and cash flows .

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies (Tables)	3 Months Ended
	Apr. 01, 2017
Fair Value Disclosures [Abstract]
Fair Value, Assets And Liabilities	The following table represents the Company's assets and liabilities that are measured at fair value on a recurring basis at April 1, 2017 (in thousands) : Quoted Prices in Active Significant Markets Other Significant for Identical Observable Unobservable Total at Assets Inputs Inputs April 1, 2017 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 522,012 $ - $ 522,012 $ - Foreign government securities 3,981 - 3,981 - Corporate debt securities 1,769,436 - 1,769,436 - Time deposits 305,462 - 305,462 - Equity securities 147 - 147 - Waters 401(k) Restoration Plan assets 32,894 32,894 - - Foreign currency exchange contracts 183 - 183 - Total $ 2,634,115 $ 32,894 $ 2,601,221 $ - Liabilities: Contingent consideration $ 3,010 $ - $ - $ 3,010 Foreign currency exchange contracts 985 - 985 - Total $ 3,995 $ - $ 985 $ 3,010 The following table represents the Company's assets and liabilities that are measured at fair value on a recu rring basis at December 31, 2016 (in thousands): Quoted Prices in Active Significant Markets Other Significant Total at for Identical Observable Unobservable December 31, Assets Inputs Inputs 2016 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury securities $ 570,313 $ - $ 570,313 $ - Foreign government securities 17,991 - 17,991 - Corporate debt securities 1,643,838 - 1,643,838 - Time deposits 199,906 - 199,906 - Equity securities 147 - 147 - Waters 401(k) Restoration Plan assets 30,954 30,954 - - Foreign currency exchange contracts 60 - 60 - Total $ 2,463,209 $ 30,954 $ 2,432,255 $ - Liabilities: Contingent consideration $ 3,007 $ - $ - $ 3,007 Foreign currency exchange contracts 730 - 730 - Total $ 3,737 $ - $ 730 $ 3,007
Summary of Derivative Instruments by Risk Exposure [Abstract]
Gains (Losses) on Foreign Exchange Contracts	The following is a summary of the activity included in cost of sales in the statements of operations related to the foreign currency exchange contracts (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Realized losses on closed contracts $ (1,438) $ (1,895) Unrealized losses on open contracts (132) (28) Cumulative net pre-tax losses $ (1,570) $ (1,923)
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): April 1, 2017 December 31, 2016 Other current assets $ 183 $ 60 Other current liabilities $ 985 $ 730
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 three months ended April 1, 2017 and April 2, 2016 (in thousands): Balance at Balance at Beginning Accruals for Settlements End of of Period Warranties Made Period Accrued warranty liability: April 1, 2017 $ 13,391 $ 1,815 $ (2,208) $ 12,998 April 2, 2016 $ 13,349 $ 1,681 $ (2,198) $ 12,832

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Apr. 01, 2017
Marketable Securities [Abstract]
Schedule of Available-for-Sale Securities Reconciliation	The Company's marketable securities within cash equivalents and investments included in the consolidated balance sheets are detailed as follows (in thousands): April 1, 2017 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 522,628 $ 96 $ (712) $ 522,012 Foreign government securities 3,981 - - 3,981 Corporate debt securities 1,770,252 916 (1,732) 1,769,436 Time deposits 305,462 - - 305,462 Equity securities 77 70 - 147 Total $ 2,602,400 $ 1,082 $ (2,444) $ 2,601,038 Amounts included in: Cash equivalents $ 219,022 $ - $ (3) $ 219,019 Investments 2,383,378 1,082 (2,441) 2,382,019 Total $ 2,602,400 $ 1,082 $ (2,444) $ 2,601,038 December 31, 2016 Amortized Unrealized Unrealized Fair Cost Gain Loss Value U.S. Treasury securities $ 570,695 $ 253 $ (635) $ 570,313 Foreign government securities 17,999 - (8) 17,991 Corporate debt securities 1,645,468 496 (2,126) 1,643,838 Time deposits 199,906 - - 199,906 Equity securities 77 70 - 147 Total $ 2,434,145 $ 819 $ (2,769) $ 2,432,195 Amounts included in: Cash equivalents $ 124,793 $ 1 $ - $ 124,794 Investments 2,309,352 818 (2,769) 2,307,401 Total $ 2,434,145 $ 819 $ (2,769) $ 2,432,195
Investments Classified By Contractual Maturity Date	The estimated fair value of marketable debt securities by maturity date is as follows (in thousands): April 1, 2017 December 31, 2016 Due in one year or less $ 1,456,067 $ 1,388,537 Due after one year through three years 839,362 843,605 Total $ 2,295,429 $ 2,232,142

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Apr. 01, 2017
Inventory Items, Net Of Reserves Alternative [Abstract]
Inventory, Net of Reserves	Inventories are classi fied as follows (in thousands): April 1, 2017 December 31, 2016 Raw materials $ 91,981 $ 95,430 Work in progress 17,598 16,585 Finished goods 170,397 150,667 Total inventories $ 279,976 $ 262,682

Goodwill and Other Intangibles

Goodwill and Other Intangibles (Tables)	3 Months Ended
	Apr. 01, 2017
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): April 1, 2017 December 31, 2016 Weighted- Weighted- Gross Average Gross Average Carrying Accumulated Amortization Carrying Accumulated Amortization Amount Amortization Period Amount Amortization Period Capitalized software $ 372,247 $ 235,359 5 years $ 355,973 $ 223,572 5 years Purchased intangibles 163,667 129,710 11 years 162,180 127,045 11 years Trademarks and IPR&D 13,623 - - 13,544 - - Licenses 5,218 4,017 6 years 4,632 3,851 6 years Patents and other intangibles 63,367 37,987 8 years 61,646 36,452 8 years Total $ 618,122 $ 407,073 7 years $ 597,975 $ 390,920 7 years

Debt (Tables)

Debt (Tables)	3 Months Ended
	Apr. 01, 2017
Debt [Abstract]
Schedule of Outstanding Debt	T he Company had the following outstanding debt a t April 1, 2017 and December 31, 2016 (in thousands) : April 1, 2017 December 31, 2016 Foreign subsidiary lines of credit $ 285 $ 297 Senior unsecured notes - Series D - 3.22%, due March 2018 100,000 - Credit agreements 125,000 125,000 Total notes payable and debt 225,285 125,297 Senior unsecured notes - Series B - 5.00%, due February 2020 100,000 100,000 Senior unsecured notes - Series D - 3.22%, due March 2018 - 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 Senior unsecured notes - Series I - 3.13%, due May 2023 50,000 50,000 Senior unsecured notes - Series J - floating rate**, due May 2024 40,000 40,000 Senior unsecured notes - Series K - 3.44%, due May 2026 160,000 160,000 Credit agreements 1,045,000 1,005,000 Unamortized debt issuance costs (2,901) (3,034) Total long-term debt 1,642,099 1,701,966 Total debt $ 1,867,384 $ 1,827,263 * Series H senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.25%. ** Series J senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.45%.

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Apr. 01, 2017
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 three months ended April 1, 2017 and April 2, 2016 (in thousands): April 1, 2017 April 2, 2016 Balance at the beginning of the period $ 9,964 $ 14,450 Net changes in uncertain tax benefits (717) (790) Balance at the end of the period $ 9,247 $ 13,660

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Apr. 01, 2017
Stock-Based Compensation [Abstract]
Schedule of Stock-Based Compensation Expense	The consolidated statements of operations for the three months ended April 1, 2017 and April 2, 2016 include the following stock-based compensation expense related to stock option awards, restricted stock awards , restricted stock unit awards, performance stock unit awards and the employee stock purchase plan (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Cost of sales $ 738 $ 671 Selling and administrative expenses 7,188 13,969 Research and development expenses 729 1,201 Total stock-based compensation $ 8,655 $ 15,841
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 three months ended April 1, 2017 and April 2, 2016 are as follows: Options Issued and Significant Assumptions Used to Estimate Option Fair Values April 1, 2017 April 2, 2016 Options issued in thousands 207 86 Risk-free interest rate 2.2% 1.5% Expected life in years 6 5 Expected volatility 0.232 0.286 Expected dividends - - Weighted-Average Exercise Price and Fair Value of Options on the Date of Grant April 1, 2017 April 2, 2016 Exercise price $ 149.74 $ 122.65 Fair value $ 40.39 $ 34.63
Stock Options Outstanding Roll Forward	T he following table summarizes stock option activity for the plans for the three months ended April 1, 2017 (in thousands, except per share data): Number of Shares Price per Share Weighted-Average Exercise Price Outstanding at December 31, 2016 2,697 $ 38.09 to $ 139.51 $ 106.55 Granted 207 $ 136.43 to $ 154.33 $ 149.74 Exercised (415) $ 41.20 to $ 128.93 $ 89.05 Canceled (43) $ 87.06 to $ 136.43 $ 113.05 Outstanding at April 1, 2017 2,446 $ 38.09 to $ 154.33 $ 113.06
Restricted Stock Units Unvested Roll Forward	Restricted Stock Units The following table summarizes the unvested restricted stock unit award activity for the three months ended April 1, 2017 (in thousands, except for per share data ): Shares Weighted-Average Price Unvested at December 31, 2016 453 $ 110.34 Granted 105 $ 154.08 Vested (131) $ 105.13 Forfeited (11) $ 111.50 Unvested at April 1, 2017 416 $ 122.99
Relevant Data Used to Determine the Value of Performance Shares	The relevant data used to determine the value of the performance stock u nits granted during 2017 is as follows: Performance Stock Units Issued and Significant Assumptions Used to Estimate Fair Values 2017 Performance stock units issued in thousands 20 Risk-free interest rate 1.5% Expected life in years 3 Expected volatility 0.232 Average volatility of peer companies 0.261 Correlation coefficient 0.385 Expected dividends -
Performance Stock Units Unvested Roll Forward	The following table summarizes the unvested performance stock unit a ward activity for the three months ended April 1, 2017 (in thousands, except for per share data ): Shares Weighted-Average Fair Value Unvested at December 31, 2016 27 $ 171.16 Granted 20 $ 198.78 Unvested at April 1, 2017 47 $ 184.40

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Apr. 01, 2017
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 April 1, 2017 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 105,557 80,073 $ 1.32 Effect of dilutive stock option, restricted stock, performance stock unit and restricted stock unit securities - 696 (0.01) Net income per diluted common share $ 105,557 80,769 $ 1.31 Three Months Ended April 2, 2016 Net Income Weighted-Average Shares Per Share (Numerator) (Denominator) Amount Net income per basic common share $ 94,052 81,275 $ 1.16 Effect of dilutive stock option, restricted stock and restricted stock unit securities - 699 (0.01) Net income per diluted common share $ 94,052 81,974 $ 1.15

Accumulated Other Comprehensi32

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Apr. 01, 2017
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income	The components of accumulated other comprehensive income are detailed as follows (in th ousands ): Currency Translation Unrealized Gain (Loss) on Retirement Plans Unrealized Gain (Loss) on Investments Accumulated Other Comprehensive Income (Loss) Balance at December 31, 2016 $ (170,566) $ (43,894) $ (1,820) $ (216,280) Other comprehensive income, net of tax 29,141 36 566 29,743 Balance at April 1, 2017 $ (141,425) $ (43,858) $ (1,254) $ (186,537)

Retirement Plans (Tables)

Retirement Plans (Tables)	3 Months Ended
	Apr. 01, 2017
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 months ended April 1, 2017 and April 2, 2016 is as follows (in thousands): Three Months Ended April 1, 2017 April 2, 2016 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 $ 101 $ 103 $ 1,251 $ 94 $ 116 $ 1,218 Interest cost 1,719 150 358 1,745 135 421 Expected return on plan assets (2,663) (147) (402) (2,417) (130) (399) Net amortization: Prior service credit - - (46) - - (45) Net actuarial loss 651 - 231 667 - 188 Net periodic pension (benefit) cost $ (192) $ 106 $ 1,392 $ 89 $ 121 $ 1,383

Business Segment Information (T

Business Segment Information (Tables)	3 Months Ended
	Apr. 01, 2017
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 months ended April 1, 2017 and April 2, 2016 (in thousands): Three Months Ended April 1, 2017 April 2, 2016 Product net sales: Waters instrument systems $ 197,789 $ 188,529 Chemistry 87,903 84,150 TA instrument systems 38,604 35,178 Total product sales 324,296 307,857 Service net sales: Waters service 157,734 151,514 TA service 15,939 15,875 Total service sales 173,673 167,389 Total net sales $ 497,969 $ 475,246

Basis of Presentation and Sum35

Basis of Presentation and Summary of Significant Accounting Policies (Details) - USD ($) shares in Millions	1 Months Ended	3 Months Ended
	May 31, 2014	Apr. 01, 2017	Apr. 02, 2016	Dec. 31, 2016
Basis of Presentation and Summary of Significant Accounting Policies [Abstract]
Long-term investments		$ 7,000,000
Acquired in-process research and development		5,000,000
Potential payments under licensing arrangements		$ 7,000,000
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		$ 2,966,000,000		$ 2,813,000,000
Derivative [Line Items]
Foreign currency exposure		The Company is a global company that operates in over 35 countries and, as a result, the Company’s net sales, cost of sales, operating expenses and balance sheet amounts are significantly impacted by fluctuations in foreign currency exchange rates. The Company is exposed to currency price risk on foreign currency exchange rate fluctuations when it translates its non-U.S. dollar foreign subsidiaries’ financial statements into U.S. dollars, and when any of the Company’s subsidiaries purchase or sell products or services in a currency other than its own currency.
Maturity period of foreign exchange contracts		The Company periodically aggregates its net worldwide balances by currency and then enters into foreign currency exchange contracts that mature within 90 days to hedge a portion of the remaining balance to minimize some of the Company’s currency price risk exposure.
Notional amount of foreign exchange contracts		$ 124,000,000		120,000,000
Realized losses on foreign exchange contracts		(1,438,000)	$ (1,895,000)
Unrealized losses on foreign exchange contracts		(132,000)	(28,000)
Cumulative net pre-tax losses on foreign exchange contracts		(1,570,000)	(1,923,000)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		2,601,038,000		2,432,195,000
Debt [Line Items]
Long-term debt		1,642,099,000		1,701,966,000
Warranty Accrual Roll Forward [Abstract]
Accrued warranty liability, balance at beginning of period		13,391,000	13,349,000
Accruals for warranties		1,815,000	1,681,000
Settlements made		(2,208,000)	(2,198,000)
Accrued warranty liability, balance at end of period		12,998,000	12,832,000
Restructuring and Related Activities [Abstract]
Restructuring charges		9,000,000	$ 3,000,000
Restructuring reserve		6,000,000
Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Waters 401(k) Restoration Plan assets		32,894,000		30,954,000
Forward foreign exchange contract assets		183,000		60,000
Fair value of total assets measured on a recurring basis		2,634,115,000		2,463,209,000
Contingent consideration		3,010,000		3,007,000
Forward foreign exchange contract liabilities		985,000		730,000
Fair value of total liabilities measured on a recurring basis		3,995,000		3,737,000
Fair Value Measurements, Recurring | Quoted Prices in Active Market for Identical Assets (Level 1) [Member]
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Waters 401(k) Restoration Plan assets		32,894,000		30,954,000
Fair value of total assets measured on a recurring basis		32,894,000		30,954,000
Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Forward foreign exchange contract assets		183,000		60,000
Fair value of total assets measured on a recurring basis		2,601,221,000		2,432,255,000
Forward foreign exchange contract liabilities		985,000		730,000
Fair value of total liabilities measured on a recurring basis		985,000		730,000
Fair Value Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		3,010,000		3,007,000
Fair value of total liabilities measured on a recurring basis		3,010,000		3,007,000
Held in currencies other than U.S. dollars [Member]
Cash Equivalents and Investments [Line Items]
Cash, cash equivalents and investments		$ 295,000,000		261,000,000
Programs authorized by Board of Directors [Member]
Stock Repurchase Program [Line Items]
Treasury stock shares acquired		0.5	0.7
Treasury stock		$ 82,000,000	$ 89,000,000
Related to Vesting of Restricted Stock Units [Member]
Stock Repurchase Program [Line Items]
Treasury stock		7,000,000	$ 6,000,000
May 2014 Program [Member]
Stock Repurchase Program [Line Items]
Stock repurchase program authorization amount	$ 750,000,000
Stock repurchase program remaining amount authorized for future purchases		41,000,000
Stock repurchase program period	3 years
US Treasury Securities | Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		522,012,000		570,313,000
US Treasury Securities | Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		522,012,000		570,313,000
Foreign Government Debt Securities | Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		3,981,000		17,991,000
Foreign Government Debt Securities | Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		3,981,000		17,991,000
Corporate Debt Securities | Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		1,769,436,000		1,643,838,000
Corporate Debt Securities | Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		1,769,436,000		1,643,838,000
Time Deposits | Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		305,462,000		199,906,000
Time Deposits | Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		305,462,000		199,906,000
Equity Securities | Fair Value Measurements, Recurring
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		147,000		147,000
Equity Securities | Fair Value Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Marketable securities		147,000		147,000
Unsecured debt
Debt [Line Items]
Long-term debt		700,000,000		700,000,000
Unsecured debt | Fixed interest rate [Member]
Debt [Line Items]
Long-term debt		610,000,000		610,000,000
Fair value of debt instrument		608,000,000		603,000,000
Held by foreign subsidiaries [Member]
Cash Equivalents and Investments [Line Items]
Cash, cash equivalents and investments		$ 2,929,000,000		$ 2,766,000,000

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	$ 2,602,400	$ 2,434,145
Unrealized Gain	1,082	819
Unrealized Loss	(2,444)	(2,769)
Fair Value	2,601,038	2,432,195
Debt securities due in one year or less	1,456,067	1,388,537
Debt securities due after one year through three years	839,362	843,605
Total debt securities	2,295,429	2,232,142
Cash Equivalents [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	219,022	124,793
Unrealized Gain		1
Unrealized Loss	(3)
Fair Value	219,019	124,794
Investments [Member]
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	2,383,378	2,309,352
Unrealized Gain	1,082	818
Unrealized Loss	(2,441)	(2,769)
Fair Value	2,382,019	2,307,401
US Treasury Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	522,628	570,695
Unrealized Gain	96	253
Unrealized Loss	(712)	(635)
US Treasury Securities | Fair Value Measurements, Recurring
Schedule of Available-for-Sale Securities [Line Items]
Fair Value	522,012	570,313
Foreign Government Debt Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	3,981	17,999
Unrealized Loss		(8)
Foreign Government Debt Securities | Fair Value Measurements, Recurring
Schedule of Available-for-Sale Securities [Line Items]
Fair Value	3,981	17,991
Corporate Debt Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	1,770,252	1,645,468
Unrealized Gain	916	496
Unrealized Loss	(1,732)	(2,126)
Corporate Debt Securities | Fair Value Measurements, Recurring
Schedule of Available-for-Sale Securities [Line Items]
Fair Value	1,769,436	1,643,838
Time Deposits
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	305,462	199,906
Time Deposits | Fair Value Measurements, Recurring
Schedule of Available-for-Sale Securities [Line Items]
Fair Value	305,462	199,906
Equity Securities
Schedule of Available-for-Sale Securities [Line Items]
Amortized Cost	77	77
Unrealized Gain	70	70
Equity Securities | Fair Value Measurements, Recurring
Schedule of Available-for-Sale Securities [Line Items]
Fair Value	$ 147	$ 147

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Inventory Items, Net Of Reserves Alternative [Abstract]
Raw materials	$ 91,981	$ 95,430
Work in progress	17,598	16,585
Finished goods	170,397	150,667
Total inventories	$ 279,976	$ 262,682

Goodwill and Other Intangible38

Goodwill and Other Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 01, 2017	Apr. 02, 2016	Dec. 31, 2016
Goodwill [Line Items]
Goodwill	$ 353,796		$ 352,080
Goodwill foreign currency translation adjustments	2,000
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	618,122		597,975
Finite-lived intangible assets, accumulated amortization	$ 407,073		$ 390,920
Finite-lived intangible assets, average useful life in years	7 years		7 years
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	$ 13,623		$ 13,544
Intangible Assets [Line Items]
Intangible assets, gross foreign currency translation adjustments	10,000
Intangible assets, accumulated amortization foreign currency translation adjustments	6,000
Amortization expense	10,000	$ 11,000
Finite-Lived Intangible Assets Future Amortization Expense [Abstract]
Future amortization expense, year 1	43,000
Future amortization expense, year 2	43,000
Future amortization expense, year 3	43,000
Future amortization expense, year 4	43,000
Future amortization expense, year 5	43,000
Capitalized software [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	372,247		355,973
Finite-lived intangible assets, accumulated amortization	$ 235,359		$ 223,572
Finite-lived intangible assets, average useful life in years	5 years		5 years
Purchased intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 163,667		$ 162,180
Finite-lived intangible assets, accumulated amortization	$ 129,710		$ 127,045
Finite-lived intangible assets, average useful life in years	11 years		11 years
Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 5,218		$ 4,632
Finite-lived intangible assets, accumulated amortization	$ 4,017		$ 3,851
Finite-lived intangible assets, average useful life in years	6 years		6 years
Patents and other intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 63,367		$ 61,646
Finite-lived intangible assets, accumulated amortization	$ 37,987		$ 36,452
Finite-lived intangible assets, average useful life in years	8 years		8 years

Debt (Details)

Debt (Details) - USD ($)	3 Months Ended	12 Months Ended
	Apr. 01, 2017	Dec. 31, 2016	Apr. 30, 2015	Jun. 30, 2013
Debt [Line Items]
Notes payable and debt	$ 225,285,000	$ 125,297,000
Long-term debt	1,642,099,000	1,701,966,000
Total debt	1,867,384,000	1,827,263,000
Line of Credit [Line Items]
Foreign subsidiary lines of credit	285,000	297,000
Line of credit maximum borrowing capacity	$ 81,000,000	$ 79,000,000
Line of credit interest rate during the period	1.48%	1.49%
Long-Term Liabilities
Debt [Line Items]
Unamortized debt issuance costs	$ (2,901,000)	$ (3,034,000)
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 D [Member]
Debt [Line Items]
Stated interest rate on debt instrument	3.22%
Notes payable and debt	$ 100,000,000
Long-term debt		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 notes - 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	$ 50,000,000	50,000,000
Senior unsecured notes - Series I [Member]
Debt [Line Items]
Stated interest rate on debt instrument	3.13%
Long-term debt	$ 50,000,000	50,000,000
Senior unsecured notes - Series J [Member]
Debt [Line Items]
Interest rate terms on debt	** Series J senior unsecured notes bear interest at a 3-month LIBOR for that floating rate interest period plus 1.45%.
Long-term debt	$ 40,000,000	40,000,000
Senior unsecured notes - Series K [Member]
Debt [Line Items]
Stated interest rate on debt instrument	3.44%
Long-term debt	$ 160,000,000	160,000,000
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 basis points 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	1,045,000,000	1,005,000,000
Unused borrowing capacity	428,000,000	468,000,000
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	$ 745,000,000
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 and J 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	$ 700,000,000	$ 700,000,000
Credit Agreements and Unsecured Debt [Member]
Debt [Line Items]
Weighted-average interest rate	2.68%	2.55%

Income Taxes (Details 1)

Income Taxes (Details 1) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Effective Income Tax Rate Reconciliation, Percent [Line Items]
Income tax holiday amount	$ 5	$ 4
Income tax holiday per share benefit	$ 0.06	$ 0.05
Effective income tax rate	7.00%	11.80%
United States [Member]
Effective Income Tax Rate Reconciliation, Percent [Line Items]
Marginal effective income tax rate	37.50%
Ireland [Member]
Effective Income Tax Rate Reconciliation, Percent [Line Items]
Marginal effective income tax rate	12.50%
United Kingdom [Member]
Effective Income Tax Rate Reconciliation, Percent [Line Items]
Marginal effective income tax rate	19.25%
Singapore [Member]
Effective Income Tax Rate Reconciliation, Percent [Line Items]
Marginal effective income tax rate	0.00%
Statutory tax rate	17.00%
ASU 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Quantification of adoption of new accounting pronouncement or change in accounting principle	$ (7)
Percentage point change in effective tax rate relating to new accounting pronouncement or change in accounting principle	(6.3)

Income Taxes (Details 2)

Income Taxes (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Unrecognized tax benefits, balance at the beginning of the period	$ 9,964	$ 14,450
Net changes in uncertain tax benefits	(717)	(790)
Unrecognized tax benefits, balance at the end of the period	9,247	$ 13,660
Expected change in unrecognized tax benefits in the next twelve months	$ (4,000)

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Stock-Based Compensation Fair Value Assumptions and Methodology [Abstract]
Weighted-average grant date fair value of options granted	$ 40.39	$ 34.63
Stock Options Outstanding Roll Forward [Abstract]
Options outstanding at beginning of period	2,697
Options granted	207	86
Options exercised	(415)
Options canceled	(43)
Options outstanding at end of period	2,446
Weighted-average exercise price of options outstanding at beginning of period	$ 106.55
Weighted-average exercise price of options granted	149.74	$ 122.65
Weighted-average exercise price of options exercised	89.05
Weighted average exercise price of options canceled	113.05
Weighted-average exercise price of options outstanding at end of period	$ 113.06
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 8,655,000	$ 15,841,000
Incremental stock-based compensation cost due to acceleration of awards	$ 7,000,000
Minimum
Stock Options Outstanding Roll Forward [Abstract]
Weighted-average exercise price of options outstanding at beginning of period	$ 38.09
Weighted-average exercise price of options granted	136.43
Weighted-average exercise price of options exercised	41.20
Weighted average exercise price of options canceled	87.06
Weighted-average exercise price of options outstanding at end of period	38.09
Maximum
Stock Options Outstanding Roll Forward [Abstract]
Weighted-average exercise price of options outstanding at beginning of period	139.51
Weighted-average exercise price of options granted	154.33
Weighted-average exercise price of options exercised	128.93
Weighted average exercise price of options canceled	136.43
Weighted-average exercise price of options outstanding at end of period	$ 154.33
Stock Options
Stock-Based Compensation Fair Value Assumptions and Methodology [Abstract]
Fair value assumptions, risk free interest rate	2.20%	1.50%
Fair value assumptions, expected life in years	6 years	5 years
Fair value assumptions, expected volatility	23.20%	28.60%
Fair value assumptions, expected dividends	$ 0	$ 0
Restricted Stock Plan
Unvested Awards Roll Forward
Shares granted	7
Weighted-average grant date fair value of shares granted	$ 136.43
Restricted Stock Unit Plan
Stock-Based Compensation by Award [Line Items]
Award vesting period	5 years
Unvested Awards Roll Forward
Unvested shares at beginning of period	453
Shares granted	105
Shares vested	(131)
Shares forfeited	(11)
Unvested shares at end of period	416
Weighted-average grant date fair value of shares unvested at beginning of period	$ 110.34
Weighted-average grant date fair value of shares granted	154.08
Weighted-average grant date fair value of shares vested	105.13
Weighted-average grant date fair value of shares forfeited	111.50
Weighted-average grant date fair value of shares unvested at end of period	$ 122.99
Performance Stock Unit Plan
Stock-Based Compensation Fair Value Assumptions and Methodology [Abstract]
Fair value assumptions, risk free interest rate	1.50%
Fair value assumptions, expected life in years	3 years
Fair value assumptions, expected volatility	23.20%
Fair value assumptions, expected volatility of peer companies	26.10%
Fair value assumptions, correlation coefficient	38.50%
Fair value assumptions, expected dividends	$ 0
Unvested Awards Roll Forward
Unvested shares at beginning of period	27
Shares granted	20
Unvested shares at end of period	47
Weighted-average grant date fair value of shares unvested at beginning of period	$ 171.16
Weighted-average grant date fair value of shares granted	198.78
Weighted-average grant date fair value of shares unvested at end of period	$ 184.40
Performance Stock Unit Plan | Minimum
Stock-Based Compensation by Award [Line Items]
Award vesting rights	0.00%
Performance Stock Unit Plan | Maximum
Stock-Based Compensation by Award [Line Items]
Award vesting rights	200.00%
Cost of sales [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 738,000	671,000
Selling and administrative expenses [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	7,188,000	13,969,000
Research and development expenses [Member]
Stock-Based Compensation Allocation of Recognized Period Expense [Line Items]
Allocated stock-based compensation expense	$ 729,000	$ 1,201,000

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Earnings Per Share Reconciliation [Abstract]
Net income	$ 105,557	$ 94,052
Net income per basic common share	$ 1.32	$ 1.16
Effect of dilutive stock option, restricted stock, performance stock unit and restricted stock unit securities on earnings per share	(0.01)	(0.01)
Net income per diluted common share	$ 1.31	$ 1.15
Weighted-average number of basic common shares	80,073	81,275
Effect of dilutive stock option, restricted stock and restricted stock unit securities on shares outstanding	696	699
Weighted-average number of diluted common shares and equivalents	80,769	81,974
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	1,100	1,200

Accumulated Other Comprehensi44

Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive loss, balance at the beginning of the period	$ (216,280)
Other comprehensive income	29,743	$ 18,779
Accumulated other comprehensive loss, balance at the end of the period	(186,537)
Currency Translation Adjustment
Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive loss, balance at the beginning of the period	(170,566)
Other comprehensive income	29,141
Accumulated other comprehensive loss, balance at the end of the period	(141,425)
Unrealized Gain (Loss) on Retirement Plans
Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive loss, balance at the beginning of the period	(43,894)
Other comprehensive income	36
Accumulated other comprehensive loss, balance at the end of the period	(43,858)
Unrealized Gain (Loss) on Investments
Accumulated Other Comprehensive Income [Line Items]
Accumulated other comprehensive loss, balance at the beginning of the period	(1,820)
Other comprehensive income	566
Accumulated other comprehensive loss, balance at the end of the period	$ (1,254)

Retirement Plans (Details)

Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Minimum
Amounts Recognized in Other Comprehensive Income [Abstract]
Estimated future employer contributions in current fiscal year	$ 6,000
Maximum
Amounts Recognized in Other Comprehensive Income [Abstract]
Estimated future employer contributions in current fiscal year	11,000
U.S. Pension Plans
Net Periodic Benefit Cost [Abstract]
Service cost	101	$ 94
Interest cost	1,719	1,745
Expected return on plan assets	(2,663)	(2,417)
Net amortization: Net actuarial loss	651	667
Net periodic pension (benefit) cost	(192)	89
U.S. Retiree Healthcare Plan
Net Periodic Benefit Cost [Abstract]
Service cost	103	116
Interest cost	150	135
Expected return on plan assets	(147)	(130)
Net periodic pension (benefit) cost	106	121
Non-U.S. Pension Plans
Net Periodic Benefit Cost [Abstract]
Service cost	1,251	1,218
Interest cost	358	421
Expected return on plan assets	(402)	(399)
Net amortization: Prior service credit	(46)	(45)
Net amortization: Net actuarial loss	231	188
Net periodic pension (benefit) cost	$ 1,392	$ 1,383

Business Segment Information (D

Business Segment Information (Details) $ in Thousands	3 Months Ended
	Apr. 01, 2017USD ($)	Apr. 02, 2016USD ($)
Business Segment Information [Line Items]
Number of operating segments	2
Number of reportable segments	1
Product sales	$ 324,296	$ 307,857
Service sales	173,673	167,389
Total net sales	497,969	475,246
Waters instrument systems [Member]
Business Segment Information [Line Items]
Product sales	197,789	188,529
Chemistry [Member]
Business Segment Information [Line Items]
Product sales	87,903	84,150
TA instrument systems [Member]
Business Segment Information [Line Items]
Product sales	38,604	35,178
Waters service [Member]
Business Segment Information [Line Items]
Service sales	157,734	151,514
TA service [Member]
Business Segment Information [Line Items]
Service sales	$ 15,939	$ 15,875

Recent Accounting Standard Ch47

Recent Accounting Standard Changes and Developments (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income per diluted common share	$ 1.31	$ 1.15
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Quantification of adoption of new accounting pronouncement or change in accounting principle	$ (7)
Net income per diluted common share	$ 0.09
Description of prior period information retrospectively adjusted as a result of new accounting pronouncement or change in accounting principle	In addition, the Company reclassified $2 million of excess tax benefits related to stock-based compensation for the first quarter of 2016 from cash flows from financing activities to cash flows from operating activities.