Stockholders' Equity - Additional Information (Detail) - USD ($)		12 Months Ended
	Nov. 21, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	May. 31, 2014	Aug. 23, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Class of warrant or right, number of securities called by warrants or rights	1,000,000					1,000,000
Warrant exercise price						$ 9.62
Warrant expiry date		Aug. 23, 2014
Warrant extended expiry period		August 23, 2017
Loss on derivative instrument		$ 0	$ 0	$ 11,652,000
Warrant exercise price	$ 9,600,000			9,620,000
Common stock authorized for issuance under the ESPP		12,040,839
Common stock available for issuance for issuance under the ESPP		5,285,862
Repurchase of available common stock, authorized amount					$ 85,000,000.0
Stock repurchase program remaining authorized repurchase amount		$ 28,739,000
1996 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting rights under 1996 Plan		The Company granted options and RSUs during 2015, 2014, and 2013 under its Restated 1996 Flexible Stock Incentive Plan. The Company also began granting options and RSUs during 2015 under the Blucora, Inc. 2015 Incentive Plan. Options and RSUs generally vest over a period of three years, with one-third vesting one year from the date of grant and the remainder vesting ratably thereafter on a semi-annual basis, and expire seven years from the date of grant. There are a few exceptions to this vesting schedule, which provide for vesting at different rates or based on achievement of performance or market targets.
Percentage of awards vested within one year from grant date		33.30%
1998 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employees contribution percentage		15.00%
Upper limit of common stock purchase under the ESPP		85.00%
Common stock authorized for issuance under the ESPP		1,360,000
Common stock available for issuance for issuance under the ESPP		200,000
Description of common stock purchase price under ESPP		The purchase price is the lesser of 85% of the fair market value of common stock on the first day or on the last day of an offering period.
Additional-paid-in capital [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrant exercise price				$ 9,620,000
Derivative instrument of liability balance	$ 20,200,000
Options and restricted stock units specified years [Member] | 1996 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Typically scheduled vesting period of 1996 Plan		3 years
Vesting period of award from grant date		1 year
Options and RSUs remainder vesting ratably thereafter description		semi-annual basis
Vesting rights expire year from the date of grant under 1996 Plan		7 years