Reconciliation of Net Amount Recognized (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Net amount recognized as at beginning of the period	$ (8,919)	$ (8,217)
Company contributions	814	703
Net periodic benefit cost for the period	(3,094)	(2,862)
Amount recognized in accumulated other comprehensive loss	(1,165)	397
Adjustments on account of employees transferred	32	20
Foreign currency translation adjustment	275	1,040
Net amount recognized as at end of the period	(12,057)	(8,919)
Funded status of the plans	0	0
Accrued benefit cost	(12,057)	(8,919)
Service cost	2,063synt_DefinedBenefitPlanServiceCosts	1,992synt_DefinedBenefitPlanServiceCosts
Interest cost	1,002us-gaap_DefinedBenefitPlanInterestCost	817us-gaap_DefinedBenefitPlanInterestCost
Amortization of transition obligation	33	30
Amortization of net actuarial (gain)/loss	(3)	23
Net periodic benefit costs	$ 3,095	$ 2,862

Defined Benefit Plan, Accrued Benefit Cost

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- Definition

Defined Benefit Plan Amounts Recognized In Accumulated Other Comprehensive Income Loss

+ References

No definition available.

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- Definition

Defined Benefit Plan, Net Periodic Benefit Costs, Current

+ References

No definition available.

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- Definition

Defined Benefit Plan, Service Costs

+ References

No definition available.

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

+ References

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- Definition

The amount of the transition obligation or asset recognized in net periodic benefit cost.

+ References

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- Definition

The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919

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- Definition

Fair value of assets transferred into (out of) a defined benefit pension plan.

+ References

No definition available.

+ Details

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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- Definition

The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(2)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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