Restatement - Balance Sheet (Details) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013		Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 281,137		$ 337,630		$ 249,523	$ 234,038
Marketable securities, current portion	6,309		5,870		6,016
Restricted cash, current portion	42		69		102
Accounts receivable, net of allowance for doubtful accounts of $0 at June 30, 2013	210,114		184,174		156,182
Unbilled revenues	116,449		85,436		92,157
Deferred tax assets, current portion					15,037
Prepaid expenses and other current assets	71,165		54,516		47,843
Total current assets	685,216		667,695		566,860
Restricted cash, net of current portion	1,664		2,019		2,392
Property and equipment, net	96,535	[1],[2]	85,898	[1],[2]	79,934
Purchased intangible assets, net	30,252		27,508		26,928
Goodwill	152,706		149,142		131,267
Other assets	27,716		18,386		21,783
Total assets	994,089		950,648		829,164
Current liabilities:
Accounts payable	33,772		30,410		29,660
Accrued expenses	79,306		65,348		57,457
Accrued compensation	83,798		99,004		68,780
Income taxes payable	7,030		18,439		3,673
Deferred revenues	28,246		29,866		22,212
Total current liabilities	232,152		243,067		181,782
Deferred tax liabilities, net of current portion					21,002
Other long-term liabilities	126,054		117,568		107,493
Total liabilities	358,206		360,635		310,277
Commitments and contingencies
Noncontrolling interest subject to put provisions	748		784		1,015	0
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000,000 shares authorized and none issued or outstanding at June 30, 2013	0		0		0
Common stock, par value $0.01 per share, 200,000,000 shares authorized, 143,966,276 shares issued, and 139,813,241 shares outstanding at June 30, 2013	1,463		1,445		1,440
Additional paid-in capital	593,613		586,673		570,679
Treasury stock, at cost, 4,153,035 shares at June 30, 2013	(48,793)		(43,756)		(43,755)
Accumulated other comprehensive loss	(29,477)		(36,551)		(42,892)
Retained earnings	118,329		81,418		32,400
Total Sapient Corporation stockholders’ equity	635,135		589,229		517,872
Total liabilities and stockholders’ equity	994,089		950,648		829,164
Parenthetical Information [Abstract]
Allowance for doubtful accounts	0		0		0
Preferred stock, par value (in dollars per share)	$ 0.01		$ 0.01		$ 0.01
Preferred stock, shares authorized	5,000,000		5,000,000		5,000,000
Preferred stock, shares issued	0		0		0
Preferred stock, shares outstanding	0		0		0
Common stock, par value (in dollars per share)	$ 0.01		$ 0.01		$ 0.01
Common stock, shares authorized	200,000,000		200,000,000		200,000,000
Common stock, shares issued	146,335,002		144,484,051		143,966,276
Common stock, shares outstanding	141,899,492		140,368,351		139,813,241
Treasury stock, shares	4,435,510		4,125,700		4,153,035
As Reported [Member]
Current assets:
Cash and cash equivalents					249,523	234,038
Marketable securities, current portion					6,016
Restricted cash, current portion					102
Accounts receivable, net of allowance for doubtful accounts of $0 at June 30, 2013					156,182
Unbilled revenues					92,157
Deferred tax assets, current portion					15,037
Prepaid expenses and other current assets					55,323
Total current assets					574,340
Restricted cash, net of current portion					2,392
Property and equipment, net					79,847
Purchased intangible assets, net					26,928
Goodwill					131,267
Other assets					9,087
Total assets					823,861
Current liabilities:
Accounts payable					29,660
Accrued expenses					56,680
Accrued compensation					84,645
Income taxes payable					10,478
Deferred revenues					22,212
Total current liabilities					203,675
Deferred tax liabilities, net of current portion					21,002
Other long-term liabilities					69,033
Total liabilities					293,710
Commitments and contingencies
Noncontrolling interest subject to put provisions					1,015
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000,000 shares authorized and none issued or outstanding at June 30, 2013					0
Common stock, par value $0.01 per share, 200,000,000 shares authorized, 143,966,276 shares issued, and 139,813,241 shares outstanding at June 30, 2013					1,440
Additional paid-in capital					570,679
Treasury stock, at cost, 4,153,035 shares at June 30, 2013					(43,755)
Accumulated other comprehensive loss					(42,892)
Retained earnings					43,664
Total Sapient Corporation stockholders’ equity					529,136
Total liabilities and stockholders’ equity					823,861
Adjustments [Member]
Current assets:
Cash and cash equivalents					0	0
Marketable securities, current portion					0
Restricted cash, current portion					0
Accounts receivable, net of allowance for doubtful accounts of $0 at June 30, 2013					0
Unbilled revenues					0
Deferred tax assets, current portion					0
Prepaid expenses and other current assets					(7,480)
Total current assets					(7,480)
Restricted cash, net of current portion					0
Property and equipment, net					87
Purchased intangible assets, net					0
Goodwill					0
Other assets					12,696
Total assets					5,303
Current liabilities:
Accounts payable					0
Accrued expenses					777
Accrued compensation					(15,865)
Income taxes payable					(6,805)
Deferred revenues					0
Total current liabilities					(21,893)
Deferred tax liabilities, net of current portion					0
Other long-term liabilities					38,460
Total liabilities					16,567
Commitments and contingencies
Noncontrolling interest subject to put provisions					0
Stockholders' equity:
Preferred stock, par value $0.01 per share, 5,000,000 shares authorized and none issued or outstanding at June 30, 2013					0
Common stock, par value $0.01 per share, 200,000,000 shares authorized, 143,966,276 shares issued, and 139,813,241 shares outstanding at June 30, 2013					0
Additional paid-in capital					0
Treasury stock, at cost, 4,153,035 shares at June 30, 2013					0
Accumulated other comprehensive loss					0
Retained earnings					(11,264)
Total Sapient Corporation stockholders’ equity					(11,264)
Total liabilities and stockholders’ equity					$ 5,303

[1] Reflects net book value of the Company’s property and equipment.

[2] Allocation of long-lived tangible assets to individual countries is based on the location of the Sapient legal entity that has title to the assets.