v2.4.0.8

Share-Based Compensation - Deferred Stock Units - Additional Information (Detail) (Deferred Stock Units [Member], USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Sep. 30, 2013	Sep. 27, 2013
Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of stock option outstanding calculated using the closing price of common stock		$ 43.52
Shares withheld to meet statutory minimum tax withholding requirements	42,094
Shares valued withheld to meet statutory minimum tax withholding requirements	$ 1.7

X

- Definition

Share based compensation arrangement by share based payment award intrinsic value closing price.

+ References

No definition available.

+ Details

Name:	syna_ShareBasedCompensationArrangementByShareBasedPaymentAwardIntrinsicValueClosingPrice
Namespace Prefix:	syna_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

No definition available.

+ Details

Name:	us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration