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, Options, Percent Of Common Stock Share Price Triggering PSO Exercises

+ References

No definition available.

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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.

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- Definition

Amount of cost for defined contribution plan.

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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.

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- Definition

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

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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- Definition

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

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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.

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

The number of grants made 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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- 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.

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- Definition

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

+ References

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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.

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- Definition

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

+ References

No definition available.

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- Definition

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

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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.

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- Definition

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

+ References

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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.

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- Definition

Number of options vested.

+ References

No definition available.

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Stock-based Compensation (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	14,693,867
Stock-based compensation expense	$ 40,626,000	$ 23,938,000	$ 22,912,000
Proceeds from employee stock purchase plan	$ 5,202,000	4,868,000	2,187,000
Stock options granted (in shares)	3,238,473
Cash received from option exercises and purchases under the ESPP	$ 12,076,000	$ 17,555,000	25,327,000
Options outstanding (in shares)	22,674,062	22,208,446
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)	850000.00%
Expenses relating to stock match	$ 3,600,000	$ 1,700,000	1,100,000
Number of shares available for issuance under 401(k) Retirement Plan (in shares)		571,674
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	$ 48,000,000
Unrecognized compensation expense weighted-average period for recognition	2 years 6 months 10 days
Intrinsic value of options exercised	$ 39,100,000	$ 85,200,000	50,000,000
Cash received from option exercises and purchases under the ESPP	12,100,000	17,600,000	25,300,000
Fair value of employee options vested and expensed	18,900,000	13,100,000	13,400,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense	$ 12,700,000
Instruments awarded (in shares)	693,131
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years
Total unrecognized compensation expense	$ 81,800,000
Unrecognized compensation expense weighted-average period for recognition	3 years 25 days
Instruments awarded (in shares)	2,519,425
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	4,722,008
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	$ 2,200,000	$ 1,600,000	$ 1,000,000
Common stock issued (in shares)	330,492	434,523	559,936
Average price per share (in dollars per share)	$ 15.74	$ 11.20	$ 3.91
Proceeds from employee stock purchase plan	$ 5,200,000	$ 4,900,000	$ 2,200,000
Performance Share Options (PSO) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	308,365
Exercise threshold, percentage of per share exercise price of the PSO	125.00%
Performance Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 0	$ 4,100,000.0
Number of options in vested (in shares)			5,870,303
Options outstanding (in shares)		0