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Percentage of payroll deduction to compensation.

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Share based compensation arrangement by share based payment award equity instruments other than options dividend reinvestment.

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Share based compensation arrangement by share based payment award maximum amount per employee.

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Percentage of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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Share based compensation arrangement by share based payment award vesting percentage maximum per quarter.

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Share based compensation arrangement minimum period of service.

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Stock exercise price as percentage of closing market price.

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Number of shares of equity interests issued or issuable to acquire entity.

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Aggregate number of common shares reserved for future issuance.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)		1 Months Ended	12 Months Ended
	Apr. 29, 2016	May 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued			53,672,861	53,199,720
Common stock reserved for issuance			18,000,000
Vesting period			3 years
Number of stock options outstanding			0	0
Number of stock options exercisable			0	0
Tax effect from stock-based plans			$ 1,254,000	$ 837,000	$ 331,000
Capitalization of share based payment costs			$ 471,000	$ 471,000
Options granted			0	0	0
Total intrinsic value of options exercised				$ 494,000	$ 958,000
Restricted stock units, weighted average grant date fair value			$ 8.52	$ 8.16	$ 6.37
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options outstanding			0
Cash received from employees as a result of employee stock option exercises				$ 592,000
Tax effect from stock-based plans				$ 21,000
Employee Stock Purchase Plan - Second Amended and Restated [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance			400,000
Percentage of Common Stock through payroll deductions			10.00%
Amount of payroll deduction			$ 21,250
Percentage of closing price of the Common Stock			85.00%
Common stock, shares issued					20,053
Common stock, exercise price					$ 24.52
Employee Stock Purchase Plan - Second Amended and Restated [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock			85.00%
Stock Incentive Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance			15,306,423
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
Stock Incentive Plans 2001 and After [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of exercise price fair value option grant in period			100.00%
Stock options granted to employees under plans prior to 2001, vested per quarter thereafter			6.25%
Stock options expired			10 years
Stock Incentive Plans 2001 and After [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to employees under plans prior to 2001, vested after one year			25.00%
1997 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description			Options granted to directors generally vested at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from the date of grant, or (3) the effective date of an acquisition.
Number of stock options outstanding			0	0
1997 Director Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 day
1997 Director Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			13 months
2014 ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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
Percentage of closing price of the Common Stock			85.00%
Common stock, shares issued			139,079	140,531	82,481
Common stock, exercise price					$ 24.33
Common stock reserved for issuance			2,137,909
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			85.00%
2014 ESPP Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price			$ 31.40	$ 30.74
2014 ESPP Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price			$ 35.16	$ 31.34
Employee Stock Purchase Plan - Third Amended and Restated [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance			1,950,000
Percentage of payroll deduction to compensation			Up to 10%
Percentage of Common Stock through payroll deductions			10.00%
Amount of payroll deduction			$ 21,250
Percentage of closing price of the Common Stock			85.00%
Common stock, shares issued					69,474
Common stock, exercise price					$ 24.52
Employee Stock Purchase Plan - Third Amended and Restated [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock			85.00%
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
Number of RSUs outstanding			17,462
Dividend reinvestment			187
Restricted stock units, weighted average grant date fair value			$ 35.62
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested			$ 18,844,000	$ 12,868,000	$ 12,106,000
Total compensation expense related to restricted stock unites and stock appreciation rights			$ 23,446,000
Estimated weighted average amortization period			11 months 5 days
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to employees under plans prior to 2001, vested after one year			33.30%	33.30%	33.30%
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 day
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			13 months
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		19,137
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 are at least 60 years old and have a minimum of 10 Years of Service (as defined in the applicable RSU agreement) are expensed immediately.
Minimum years of service for RSU			10 years
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			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.
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			$ 18,844,000	$ 12,868,000	$ 12,106,000
Total compensation expense related to restricted stock unites and stock appreciation rights			$ 23,446,000
Estimated weighted average amortization period			11 months 5 days
Employee Stock Option [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			$ 18,844,000	$ 12,868,000	$ 12,106,000
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] \| Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement	899,851