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Employee Benefit Plans and Stock-based Compensation - Additional Information (Detail) |  | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 09, 2016 shares | Sep. 30, 2016 USD ($) $ / shares shares | Jul. 01, 2016 USD ($) | Oct. 02, 2015 USD ($) $ / shares | Sep. 30, 2016 USD ($) $ / shares shares | Oct. 02, 2015 USD ($) $ / shares | Dec. 31, 2015 | Feb. 29, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Increase in authorized shares reserved for issuance | shares |  |  |  |  | 2,000,000 |  |  |
Intrinsic value of options exercised |  | $ 100,000 |  | $ 0 | $ 100,000 | $ 1,700,000 |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 2.00% |  |  | 2.00% |  |  |
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax |  | $ 0 |  |  | $ 0 |  |  |
Pension and Other Postretirement Benefit Contributions |  | 0 |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost |  | 99,000 |  |  | $ 233,000 |  |  |
Discretionary contributions of plan |  |  |  |  | 25.00% |  |  |
Percent of employees' gross pay eligible for matching |  |  |  |  | 4.00% |  |  |
Maximum contribution amount per participant |  |  |  |  | $ 1,000 |  |  |
Contributions in period |  |  |  |  | 316,000 | $ 342,000 |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized |  | $ 11,700,000 |  |  | 11,700,000 |  |  |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition |  | 1 year 9 months 18 days |  |  |  |  |  |
Defined Benefit Plan, Accumulated Benefit Obligation |  | $ 5,000,000 |  |  | $ 5,000,000 |  |  |
Stock Options [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares |  | $ 1.00 |  | $ 2.01 | $ 0.97 | $ 2.63 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value |  | $ 400,000 |  | $ 600,000 | $ 1,800,000 | $ 2,500,000 |  |
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options |  | 0 |  | 0 | 0 | 0 |  |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value |  | $ 1,600,000 |  | $ 2,200,000 | $ 8,600,000 | $ 9,900,000 |  |
Performance-based Restricted Stock Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures | shares |  | 898,533 |  |  |  |  |  |
Employee Stock Purchase Plan |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Increase in authorized shares reserved for issuance | shares | 1,500,000 |  |  |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance | shares |  | 906,390 |  |  | 906,390 |  |  |
Discount Percentage On Purchase Of Stock |  | 15.00% |  |  |  |  |  |
Percentage of fair market value of Common Stock to purchase shares |  | 85.00% |  |  |  |  |  |
Value Of Stock Purchase Right Percentage Of Put Option |  | 15.00% |  |  |  |  |  |
TVN [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Business Combination Assumed Equity Benefit Plan |  |  |  |  |  |  |  | 2
Fair Value of Employee Equity Benefit Plan Liabilities |  | $ 18,365,000 |  |  | $ 18,365,000 |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 2.00% |  |  | 2.00% |  |  |
TVN [Member] | Maximum [Member] | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Increase in authorized shares reserved for issuance | shares |  |  |  |  | 1,750,000 |  |  |
Scenario, Plan [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Defined Benefit Plan, Settlements, Benefit Obligation |  |  |  |  | $ 1,600,000 |  |  |
Assumed Employee Equity Plans [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Other Payments to Acquire Businesses |  |  | $ 2,900,000 |  |  |  |  |
Stock Plan 1995 [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Increase in authorized shares reserved for issuance | shares | 2,000,000 |  |  |  |  |  |  |
Euro Zone AA Rated [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Long-term Euro zone AA rated, Term |  |  |  |  |  |  | 10 years |
Long-term Euro zone AA rated 10 years corporate bonds yield |  |  |  |  |  |  | 2.00% |

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- Definition Defined Contribution Plan Employer Discretionary Maximum Contribution Amount Per Participant + References No definition available. + Details
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- Definition The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (j-k) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e681-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503844 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Net number of share options (or share units) granted during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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