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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Jan. 31, 2017	Apr. 29, 2016	May 31, 2018	May 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance					18,000,000
Restricted stock units, weighted average grant date fair value					$ 16.04	$ 21.74	$ 13.14
Capitalization of share based payment costs					$ 1,595	$ 471	$ 471
Vesting period					3 years
Common Stock, Shares, Issued					54,596,183	54,039,554
2014 ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance					1,800,324
Shares authorized for issuance					2,500,000
Percentage of payroll deduction to compensation					up to 10%
Percentage of Common Stock through payroll deductions					10.00%
Amount of payroll deduction					$ 21,250
Amount of payroll deduction increased					$ 22,500
Percentage of closing price of the Common Stock					85.00%		90.00%
Common Stock, Shares, Issued					126,407	105,672	105,506
2014 ESPP Plan [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock	90.00%				85.00%
2014 ESPP Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price					$ 64.31	$ 84.11	$ 46.37
2014 ESPP Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price					$ 63.78	$ 70.61	$ 74.12
Stock Incentive Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance					13,268,546
Shares available for future grant					18,000,000
Percentage of exercise price fair value option grant in period					100.00%
Number of shares returned for each common stock					2.4
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement					1,260,525
Restricted stock units, weighted average grant date fair value					$ 87.11
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested					$ 68,123	$ 61,626	$ 60,302
Total compensation expense related to restricted stock unites and stock appreciation rights					$ 26,137
Estimated weighted average amortization period					1 year
Dividend reinvestment					57	66	122
Number of RSUs outstanding					5,794	6,694	12,134
Vesting percentage per year of RSUs from date of grant					33.00%
Shares available for future grant					18,000,000
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage per year of RSUs from date of grant					33.00%	33.00%	33.00%
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Level of performance target achieved					0.00%
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Level of performance target achieved					150.00%
Restricted Stock Units (RSUs) [Member] \| Newport Deferred Compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend reinvestment					3,086
Number of RSUs outstanding					327,328
Restricted Stock Units (RSUs) [Member] \| Newport Deferred Compensation [Member] \| Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Newport RSUs converted to MKS RSUs at Merger date					36,599
Newport RSUs converted to MKS RSUs at Merger date and released			5,561	5,515	967
Restricted Stock Units (RSUs) [Member] \| ESI Plan member [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement					748,920
Restricted Stock Units (RSUs) [Member] \| ESI Plan member [Member] \| Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Newport RSUs converted to MKS RSUs at Merger date					326,283
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested					$ 68,123	$ 61,626	$ 60,302
Total compensation expense related to restricted stock unites and stock appreciation rights					$ 26,137
Estimated weighted average amortization period					1 year
RSUs Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description					employees who meet certain retirement eligibility requirements will vest in full upon each such employee’s retirement and are expensed immediately
RSUs Granted To Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description					RSUs granted to directors generally vest at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of a change in control of the Company.
Newport [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement		360,674
Newport [Member] \| Restricted Stock Units (RSUs) [Member] \| ESI Plan member [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement		736,133
Newport [Member] \| Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement		899,851
Newport [Member] \| Stock Appreciation Rights (SARs) [Member] \| ESI Plan member [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement		12,787