Income Taxes - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended					6 Months Ended		12 Months Ended											3 Months Ended	6 Months Ended				6 Months Ended		6 Months Ended	12 Months Ended		6 Months Ended						1 Months Ended	3 Months Ended
	Jul. 13, 2011	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2010	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2010	Dec. 31, 2012	Dec. 31, 2007	Dec. 31, 2005	Dec. 31, 2004	Dec. 31, 2003	Dec. 31, 2002	Dec. 31, 2009 Software Development Entity	Apr. 30, 2008 Tax Exemption Period Entity	Mar. 31, 2013 Mumbai Tax Exemption Period Entity	Mar. 31, 2013 Mumbai Completion of Tax Holiday Period Entity	Mar. 31, 2013 India	Jun. 30, 2013 India	Jun. 30, 2013 India Minimum	Jun. 30, 2013 India Maximum	Jun. 30, 2013 Minimum Alternate Tax (MAT)	Jun. 30, 2013 Scenario, Adjustment from the Finance Bill 2013 India	Jun. 30, 2013 Local Jurisdiction	Jun. 30, 2013 Syntel Europe Limited	Dec. 31, 2012 Syntel Europe Limited	Jun. 30, 2013 Other Disputes	Jun. 30, 2013 Certain Units In Sez First Five Years	Jun. 30, 2013 Certain Units In Sez Additional Two Years	Jun. 30, 2013 Certain Units In Sez Additional Three Years	Jun. 30, 2013 New Units In Sez First Five Years	Jun. 30, 2013 New Units In Sez Next Five Years	Jun. 30, 2013 New Units In Sez Another Five Years	Apr. 30, 2008 Three Units in Mumbai First Five Years	Mar. 31, 2013 Three Units in Mumbai First Five Years	Mar. 31, 2013 Unit in Chennai First Five Years Entity
Income Taxes [Line Items]
Statutory rate		35.00%			35.00%		35.00%	35.00%
Expense recognized for accrued interest and penalties		$ 10,000
Accrued interest and penalties related to unrecognized tax benefits		1,320,000					1,320,000			1,400,000
Income taxes paid against liabilities for unrecognized tax benefits		22,850,000					22,850,000			20,580,000
Unrecognized tax liability		26,860,000					26,860,000			24,940,000
Unrecognized tax benefits, tax disputes							1,540,000
Unrecognized tax benefits, potential tax disputes							2,980,000
Corporate income taxes, exemption percentage																														100.00%	50.00%	50.00%	100.00%	50.00%	50.00%	50.00%	100.00%	100.00%
Number of units																1	4	6	1																			1
Exemption from corporate income taxes							10 years
Corporate income taxes, years							15 years
Unrecognized Indian income tax liabilities														4,660,000	4,660,000														1,550,000
Income tax liability recognized												740,000	740,000																800,000
Income tax adjustments provision reversal									330,000
Reversal of provision of uncertain tax liability							240,000
Incurred losses of subsidiary																											2,620,000	1,960,000
Deferred tax assets																											550,000	430,000
Valuation allowance																											550,000	430,000
Branch Profit Tax (BPT)							15.00%
Accumulated deferred tax liability on BPT											1,730,000
Additional branch profit taxes if profits were not permanently invested		6,350,000					6,350,000
Accrued taxes, likely amount		186,200,000					186,200,000
Income tax audit, service tax objection amount				460,000		3,850,000	5,510,000
Service tax audit objection received	3,000,000
Closure of service tax audit objection amount		850,000					850,000
Received service tax refund			160,000
Service tax return with show cause notice							2,040,000
Service tax demand including penalty		3,950,000					3,950,000
Interest percentage on service tax penalty							18.00%
Surcharge rate																					5.00%				10.00%
Corporation tax rate																				32.45%	33.99%
Dividend distribution tax																					16.22%				16.99%
Minimum alternative tax																					20.01%				20.96%
Deferred tax credit		400,000
Deferred tax additional charge		500,000
Increase in Cost Inflation Index																						4.00%	11.00%
Deferred tax assets and credit to the tax expenses																					550,000			16,260,000
Local tax liability																										20,000
Local tax liability gross			190,000							4,300,000
Local tax liability net										$ 2,700,000
Minimum alternate tax credit expiration period																								10 years