XML 71 R41.htm IDEA: XBRL DOCUMENT v3.3.0.814

Auction Rate Securities - ARS Investments (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Jun. 30, 2015
Amortized Cost And Fair Value Debt Securities [Abstract]
Investment securities accretion	$ 3.1	$ 2.7

X

- Definition

Accumulated accretion on investment securities.

+ References

No definition available.

+ Details

Name:	syna_AccumulatedAccretionOnInvestmentSecurities
Namespace Prefix:	syna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amortized cost and fair value debt securities.

+ References

No definition available.

+ Details

Name:	syna_AmortizedCostAndFairValueDebtSecuritiesAbstract
Namespace Prefix:	syna_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration