Contractual interest rate for funds borrowed, under the debt agreement.

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Commitments and Contingencies - Convertible Senior Notes Due 2014 (Details) - USD ($) $ in Millions	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2017
Fiscal Years
Remainder of 2019	$ 0.6
2020	1.1
2021	1.1
2022	1.1
2023	1.1
Thereafter	451.2
Net carrying amount of the liability component	$ 456.2
2024 Notes \| Convertible Debt
Debt Instrument [Line Items]
Debt, stated interest rate	0.25%		0.25%
Fiscal Years
Net carrying amount of the liability component	$ 338.5	$ 334.2