Investments (Tables)

3 Months Ended

Apr. 01, 2017

Investments, Debt and Equity Securities [Abstract]

The following table summarizes our investments:



	April 1, 2017								December 31, 2016
	Amortized Cost		Accumulated Other Comprehensive Income				Estimated Fair Value		Amortized Cost		Accumulated Other Comprehensive Income				Estimated Fair Value
Available-for-sale securities (in thousands)	Amortized Cost		Gains		Losses		Estimated Fair Value		Amortized Cost		Gains		Losses		Estimated Fair Value
Commercial paper	$	31,702	$	2	$	25	$	31,679	$	23,744	$	—	$	60	$	23,684
Money market funds	2,189		—		—		2,189		2,266		—		—		2,266
U.S. treasury bills and notes	10,485		—		8		10,477		29,467		1		7		29,461
Securities and obligations of U.S. government agencies	134,487		11		317		134,181		127,961		8		265		127,704
Total	$	178,863	$	13	$	350	$	178,526	$	183,438	$	9	$	332	$	183,115

Fair Value, by Balance Sheet Grouping

The following table identifies the balance sheet classifications of our investments:



(In thousands)	April 1, 2017		December 31, 2016
Cash equivalents	$	24,129	$	2,266
Short-term investments	154,397		180,849
Investments, at estimated fair value	$	178,526	$	183,115

Investments Classified by Contractual Maturity Date

The gross amortized cost and estimated fair value of our investments at April 1, 2017 and December 31, 2016, by contractual maturity, are shown below. Expected maturities will differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.



	April 1, 2017				December 31, 2016
(In thousands)	Gross Amortized Cost		Fair Value		Gross Amortized Cost		Fair Value
Due in one year or less	$	122,738	$	122,577	$	112,164	$	112,058
Due after one year through five years	56,125		55,949		71,274		71,057
Total	$	178,863	$	178,526	$	183,438	$	183,115

Schedule of Temporary Impairment Losses, Investments

The following table provides the breakdown of the cash equivalents and investments with unrealized losses at April 1, 2017:



	In Loss Position for Less Than 12 Months				Total
(In thousands)	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Commercial papers	14,272		25		14,272		25
U.S. treasury bills and notes	$	10,477	$	8	$	10,477	$	8
Securities and obligations of U.S. government agencies	119,679		317		119,679		317
Total	$	144,428	$	350	$	144,428	$	350

The following table provides the breakdown of the cash equivalents and investments with unrealized losses at December 31, 2016:



	In Loss Position for Less Than 12 Months				Total
(In thousands)	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Commercial papers	$	17,693	$	60	$	17,693	$	60
U.S. treasury bills and notes	$	18,463	$	7	$	18,463	$	7
Securities and obligations of U.S. government agencies	$	103,426	$	265	$	103,426	$	265
Total	$	139,582	$	332	$	139,582	$	332

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details