Balance Sheets Components (Amortized Cost and Fair Value) (Details) $ in Thousands	Oct. 01, 2017 USD ($)
Amortized Cost
Due in one year or less	$ 40,663
Due after one year to five years	47,379
Total, amortized cost basis	88,042
Fair Value
Due in one year or less	40,652
Due after one year to five years	47,370
Total, fair value	$ 88,022