An element designated to encapsulate any additional information related to cash and cash equivalents not otherwise addressed by the existing taxonomy. Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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Basis of Presentation and Summary of Significant Accounting Policies (Details) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended		9 Months Ended			9 Months Ended			1 Months Ended		9 Months Ended		29 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013	Dec. 31, 2013	Sep. 27, 2014 Programs authorized by Board of Directors [Member]	Sep. 27, 2014 Related To Vesting Of Restricted Stock Units [Member]	Sep. 28, 2013 Related To Vesting Of Restricted Stock Units [Member]	May 31, 2014 May 2014 Program [Member]	May 31, 2014 May 2012 Program [Member]	Sep. 27, 2014 May 2012 Program [Member]	Sep. 28, 2013 May 2012 Program [Member]	Sep. 27, 2014 May 2012 Program [Member]	Sep. 27, 2014 Unsecured debt [Member]	Dec. 31, 2013 Unsecured debt [Member]	Sep. 27, 2014 Held by foreign subsidiaries [Member]	Dec. 31, 2013 Held by foreign subsidiaries [Member]	Sep. 27, 2014 US Treasury Securities	Dec. 31, 2013 US Treasury Securities	Sep. 27, 2014 Foreign Government Debt Securities	Dec. 31, 2013 Foreign Government Debt Securities	Sep. 27, 2014 Corporate Debt Securities	Dec. 31, 2013 Corporate Debt Securities	Sep. 27, 2014 Time Deposits	Dec. 31, 2013 Time Deposits	Sep. 27, 2014 Equity Securities	Dec. 31, 2013 Equity Securities	Sep. 27, 2014 Significant Other Observable Inputs (Level 2)	Dec. 31, 2013 Significant Other Observable Inputs (Level 2)	Sep. 27, 2014 Significant Other Observable Inputs (Level 2) US Treasury Securities	Dec. 31, 2013 Significant Other Observable Inputs (Level 2) US Treasury Securities	Sep. 27, 2014 Significant Other Observable Inputs (Level 2) Foreign Government Debt Securities	Dec. 31, 2013 Significant Other Observable Inputs (Level 2) Foreign Government Debt Securities	Sep. 27, 2014 Significant Other Observable Inputs (Level 2) Corporate Debt Securities	Dec. 31, 2013 Significant Other Observable Inputs (Level 2) Corporate Debt Securities	Sep. 27, 2014 Significant Other Observable Inputs (Level 2) Time Deposits	Dec. 31, 2013 Significant Other Observable Inputs (Level 2) Time Deposits	Sep. 27, 2014 Significant Other Observable Inputs (Level 2) Equity Securities	Dec. 31, 2013 Significant Other Observable Inputs (Level 2) Equity Securities	Sep. 27, 2014 Significant Unobservable Inputs (Level 3)
Derivative [Line Items]
Notional amount of foreign exchange contracts	$ 105,000,000		$ 105,000,000		$ 104,000,000
Cumulative net pre-tax gains (losses) on foreign exchange contracts	(309,000)	2,326,000	(1,366,000)	5,658,000
Realized gains (losses) on foreign exchange contracts	(266,000)	1,837,000	(366,000)	5,866,000
Unrealized (losses) gains on foreign exchange contracts	(43,000)	489,000	(1,000,000)	(208,000)
Fair Value of Assets and Liabilities Measured on a Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents and Investments, Fair Value	1,628,105,000		1,628,105,000		1,399,840,000													578,452,000	556,539,000	49,992,000	139,670,000	935,298,000	629,434,000	64,216,000	74,050,000	147,000	147,000			578,452,000	556,539,000	49,992,000	139,670,000	935,298,000	629,434,000	64,216,000	74,050,000	147,000	147,000
Other cash equivalents	33,001,000		33,001,000		62,851,000																							33,001,000	62,851,000
Waters 401(k) Restoration Plan assets	32,653,000		32,653,000		31,203,000																							32,653,000	31,203,000
Forward foreign exchange contract assets	279,000		279,000		929,000																							279,000	929,000
Fair value of total assets measured on a recurring basis	1,694,038,000		1,694,038,000		1,494,823,000																							1,694,038,000	1,494,823,000
Contingent consideration	3,336,000		3,336,000																																					3,336,000
Forward foreign exchange contract liabilities	439,000		439,000		88,000																							439,000	88,000
Fair value of total liabilities measured on a recurring basis	3,775,000		3,775,000		88,000																							439,000	88,000											3,336,000
Property, Plant and Equipment [Line Items]
Real Estate Impairment			4,000,000
Fair value of building held-for-sale	5,000,000		5,000,000
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	1,946,000,000		1,946,000,000		1,804,000,000											1,899,000,000	1,738,000,000
Debt [Line Items]
Long-term debt	1,205,000,000		1,205,000,000		1,190,000,000									600,000,000	400,000,000
Fair value of debt instruments														605,000,000	398,000,000
Stock Repurchase Program [Line Items]
Stock repurchase program authorization amount									750,000,000
Treasury stock shares acquired											2.4	2.3	6.8
Treasury stock							7,000,000	6,000,000			255,000,000	220,000,000	657,000,000
Stock repurchase program remaining amount authorized for future purchases						843,000,000				221,000,000
Stock repurchase program period, in years									3 years
Warranty Accrual Roll Forward [Abstract]
Accrued warranty liability, balance at beginning of period			12,962,000	12,353,000
Accruals for warranties			5,292,000	5,384,000
Settlements made			(5,773,000)	(5,773,000)
Accrued warranty liability, balance at end of period	$ 12,481,000	$ 11,964,000	$ 12,481,000	$ 11,964,000