v2.4.0.6

Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended				9 Months Ended
	Mar. 30, 2012	Apr. 01, 2011	Mar. 30, 2012	Apr. 01, 2011	Mar. 30, 2012 Seagate Technology plc 2012 Equity Incentive Plan M	Oct. 26, 2011 Seagate Technology plc 2012 Equity Incentive Plan	Mar. 30, 2012 Options or share appreciation rights	Mar. 30, 2012 Full-Value Share Awards	Nov. 03, 2011 Seagate Technology 2004 Share Compensation Plan
Compensation
Stock-based compensation	$ 12	$ 12	$ 38	$ 38
Issuance of ordinary shares
Common stock available for issuance under plan (in shares)					36,900,000	11,041,148			11,041,148
Ordinary shares issuable under plan						27,000,000
Par value of ordinary shares registered under Share Compensation Plan (in dollars per share)						$ 0.0001
Minimum vesting period (in years)								D3Y
Maximum vesting period (in years)								D4Y
Percentage of options vested on the first anniversary of the vesting commencement date					25.00%
Percentage of options vested proportionately over the next 36 months of the vesting commencement date					75.00%
Remaining award vesting period (in months)					36
Number of shares counted against Share Reserve for every one share granted under EIP							1	2.1
Number of shares granted under EIP					1

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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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The maximum vesting term over 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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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

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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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