Marketable Securities (Notes)

12 Months Ended

Sep. 28, 2018

Investments, Debt and Equity Securities [Abstract]

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

4.    MARKETABLE SECURITIES

The Company's portfolio of available-for-sale marketable securities consists of the following (in millions):

	Current				Noncurrent
Available for sale:	September 28, 2018		September 29, 2017		September 28, 2018		September 29, 2017
U.S. Treasury and government	$	65.0	$	—	$	—	$	—
Corporate bonds and notes	204.1		—		12.0		—
Municipal bonds	2.0		—		0.8		—
Other government	23.0		—		10.0		—
Total	$	294.1	$	—	$	22.8	$	—

The contractual maturities of noncurrent available-for-sale marketable securities were due within two years or less.

The Company recorded unrealized gains and losses on sales of available-for-sale marketable securities as follows (in millions):

September 28, 2018	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. Treasury and government	$	65.0	$	—	$	—		$	65.0
Corporate bonds and notes	216.1		—		(0.1		)	216.0
Municipal bonds	2.8		—		—			2.8
Other government	33.1		—		—			33.1
Total	$	317.0	$	—	$	(0.1	)	$	316.9

The Company concluded that the unrealized losses were temporary at September 28, 2018. Further, for bonds and other debt securities held by the Company with unrealized losses, the Company did not have the intent to sell, nor was it more likely than not that the Company would be required to sell, such securities before recovery or maturity.