Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Net revenue	$ 417.4	$ 386.2
Cost of revenue	303.0	262.8
Gross margin	114.4	123.4
Operating expenses:
Research and development	87.1	73.4
Selling, general, and administrative	40.3	34.6
Acquired intangibles amortization	4.1	4.5
Restructuring	(0.2)	5.3
Total operating expenses	131.3	117.8
Operating income/(loss)	(16.9)	5.6
Interest and other income/(expense), net	(6.0)	(0.9)
Income/(loss) before provision for income taxes and equity investment loss	(22.9)	4.7
Provision for income taxes	3.2	1.0
Equity investment loss	(0.4)
Net income/(loss)	$ (26.5)	$ 3.7
Net income/(loss) per share:
Basic	$ (0.79)	$ 0.11
Diluted	$ (0.79)	$ 0.10
Shares used in computing net income/(loss) per share:
Basic	33.5	34.8
Diluted	33.5	35.6

Amortization of intangible assets included in operating expense.

No definition available.

Name:	syna_AmortizationOfIntangibleAssetsIncludedInOperatingExpense
Namespace Prefix:	syna_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.