Defined Contribution Plan, Number of Shares Available for Grant

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- Definition

Share-based compensation arrangement by share-based payment award, options, vested and expensed, fair value.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date, Purchase Period

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Exercise Period Extension

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Termination Period Prior to Change in Control

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Termination Period Subsequent to Change in Control

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ 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=96867065&loc=d3e5070-113901

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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

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

+ Details

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

+ Details

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- Definition

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.

+ References

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- Definition

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.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

+ Details

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- Definition

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.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Number of options vested.

+ References

No definition available.

+ Details

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Stock-based Compensation (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 29, 2017	Dec. 30, 2016	Jan. 01, 2016	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	20,328,545
Stock-based compensation expense	$ 23,938,000	$ 22,912,000	$ 21,977,000
Proceeds from employee stock purchase plan	4,868,000	2,187,000	568,000
Cash received from option exercises and purchases under the ESPP	$ 17,555,000	$ 25,327,000	10,911,000
Options outstanding (in shares)	22,208,446	24,999,665
Retirement Plan, employee contribution (as a percent)	50.00%
Employer matching contributions for first 3% of participant contributions (as a percent)	100.00%
Percentage of participant contributions into the 401(k) Retirement Plan (as a percent)	3.00%
Expenses relating to stock match	$ 1,700,000	$ 1,100,000	400,000
Number of shares available for issuance under 401(k) Retirement Plan (in shares)	231,090
Change in Control and Severance Benefit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Termination period prior to change in control	1 month
Termination period subsequent to change in control	13 months
Change in Control and Severance Benefit Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Extension of exercise period	1 year
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years			10 years
Life of stock options granted	7 years
Total unrecognized compensation expense	$ 39,700,000
Unrecognized compensation expense weighted-average period for recognition	2 years 6 months 25 days
Intrinsic value of options exercised	$ 85,200,000	50,000,000	2,900,000
Cash received from option exercises and purchases under the ESPP	17,600,000	25,300,000	10,900,000
Fair value of employee options vested and expensed	$ 13,100,000	13,400,000	18,900,000
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years
Total unrecognized compensation expense	$ 61,200,000
Unrecognized compensation expense weighted-average period for recognition	3 years 2 months 12 days
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	5,052,500
Discount rate from market value on purchase date (as a percent)	85.00%
Discount rate from market value on offering date (as a percent)	85.00%
Purchase period	6 months
Stock-based compensation expense	$ 1,600,000	$ 1,000,000	$ 400,000
Common stock issued (in shares)	434,523	559,936	324,315
Average price per share (in dollars per share)	$ 11.20	$ 3.91	$ 1.75
Proceeds from employee stock purchase plan	$ 4,900,000	$ 2,200,000	$ 600,000
Performance Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 0	$ 4,100,000	$ 13,200,000
Number of options in vested (in shares)		5,870,303	6,982,613
Options outstanding (in shares)	0