Stock-Based Compensation - Stock-Based Compensation Expense in Consolidated Statements of Operations (Detail) (USD $)
In Thousands, unless otherwise specified

3 Months Ended

6 Months Ended

Mar. 29, 2014

Mar. 30, 2013

Mar. 29, 2014

Mar. 30, 2013

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

$ 12,372

$ 19,013

$ 26,098

$ 31,079

Cost of Revenues [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

2,133

1,723

3,643

3,557

Research and Development [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

2,224

2,015

4,097

3,883

Selling and Marketing [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

2,352

2,567

4,101

4,768

General and Administrative [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

5,663

5,739

9,496

11,680

Restructuring [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based compensation expense

$ 6,969

$ 4,761

$ 7,191