Cash, Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2016	Jan. 03, 2015
Available-for-sale securities
Total Cost	$ 191,913
Cash, cash equivalents and investments
Auction-rate securities guaranteed by the U.S. government	6,000
Auction-rate securities privately insured	2,000
Auction-rate securities having credit rating 'AA'	6,000
Auction-rate securities having credit rating 'A'	2,000
Other-than-temporary impairment losses	0
Cash on hand, Cost	59,071	$ 52,144
Cash on hand, Fair Value	59,071	52,144
Cash and cash equivalents, Cost	114,084	141,705
Cash and cash equivalents, Gross Unrealized Gains	1	1
Cash and cash equivalents, Fair Value	114,085	141,706
Cash Equivalents:
Available-for-sale securities
Total Cost	55,013	89,561
Available-for-sale securities, Gross Unrealized Gains	1	1
Available-for-sale securities, Fair Value	55,014	89,562
Short-term Investments:
Available-for-sale securities
Total Cost	128,900	193,365
Available-for-sale securities, Gross Unrealized Losses	(42)	(73)
Available-for-sale securities, Gross Unrealized Gains	43	197
Available-for-sale securities, Fair Value	128,901	193,489
Long-term Investments:
Available-for-sale securities
Total Cost	8,000	8,000
Available-for-sale securities, Gross Unrealized Losses	(874)	(581)
Available-for-sale securities, Fair Value	7,126	7,419
Money market funds \| Cash Equivalents:
Available-for-sale securities
Total Cost	37,721	71,415
Available-for-sale securities, Fair Value	37,721	71,415
Certificates of deposit \| Cash Equivalents:
Available-for-sale securities
Total Cost	2,845	7,739
Available-for-sale securities, Fair Value	2,845	7,739
Certificates of deposit \| Short-term Investments:
Available-for-sale securities
Total Cost	8,000	250
Available-for-sale securities, Fair Value	8,000	250
Municipal bonds \| Cash Equivalents:
Available-for-sale securities
Total Cost	1,576	1,756
Available-for-sale securities, Gross Unrealized Gains	1	1
Available-for-sale securities, Fair Value	1,577	1,757
Municipal bonds \| Short-term Investments:
Available-for-sale securities
Total Cost	93,506	129,005
Available-for-sale securities, Gross Unrealized Losses	(32)	(25)
Available-for-sale securities, Gross Unrealized Gains	42	172
Available-for-sale securities, Fair Value	93,516	129,152
Commercial paper \| Cash Equivalents:
Available-for-sale securities
Total Cost	11,272	5,348
Available-for-sale securities, Fair Value	11,272	5,348
Commercial paper \| Short-term Investments:
Available-for-sale securities
Total Cost	11,176	8,995
Available-for-sale securities, Fair Value	11,176	8,995
Asset-backed securities \| Short-term Investments:
Available-for-sale securities
Total Cost		5,380
Available-for-sale securities, Gross Unrealized Losses		(3)
Available-for-sale securities, Fair Value		5,377
Variable-rate demand notes \| Short-term Investments:
Available-for-sale securities
Total Cost	8,995	12,915
Available-for-sale securities, Fair Value	8,995	12,915
International government bonds \| Short-term Investments:
Available-for-sale securities
Total Cost	2,227	2,526
Available-for-sale securities, Gross Unrealized Losses	(7)	(10)
Available-for-sale securities, Fair Value	2,220	2,516
Corporate bonds \| Cash Equivalents:
Available-for-sale securities
Total Cost		1,101
Available-for-sale securities, Fair Value		1,101
Corporate bonds \| Short-term Investments:
Available-for-sale securities
Total Cost	999	33,043
Available-for-sale securities, Gross Unrealized Losses	(3)	(35)
Available-for-sale securities, Gross Unrealized Gains		25
Available-for-sale securities, Fair Value	996	33,033
U.S. government bonds \| Cash Equivalents:
Available-for-sale securities
Total Cost		1,000
Available-for-sale securities, Fair Value		1,000
U.S. government bonds \| Short-term Investments:
Available-for-sale securities
Total Cost		650
Available-for-sale securities, Fair Value		650
US government agency \| Cash Equivalents:
Available-for-sale securities
Total Cost	1,599	1,202
Available-for-sale securities, Fair Value	1,599	1,202
US government agency \| Short-term Investments:
Available-for-sale securities
Total Cost	3,997	601
Available-for-sale securities, Gross Unrealized Gains	1
Available-for-sale securities, Fair Value	3,998	601
Auction rate securities \| Long-term Investments:
Available-for-sale securities
Total Cost	8,000	8,000
Available-for-sale securities, Gross Unrealized Losses	(874)	(581)
Available-for-sale securities, Fair Value	$ 7,126	$ 7,419

This element represents the amount of auction-rate securities that is guaranteed by the U.S. government.

No definition available.

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- Definition

This element represents the amount of auction-rate securities having credit rating of 'A'.

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This element represents the amount of auction-rate securities having credit rating of 'AA'.

+ References

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- Definition

This element represents the amount of auction-rate securities that is privately insured.

+ References

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- Definition

This element represents the adjusted cost of cash and cash equivalents that are considered available-for-sale and recorded at fair value.

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No definition available.

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This element represents the unrealized gains from cash and cash equivalents.

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- Definition

Represents fair value of cash which is similar to carrying value of cash as of balance sheet date.

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No definition available.

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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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.

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No definition available.

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