Exercise price as percentage of fair value of of the ordinary share on the date of grant.

No definition available.

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- Definition

Minimum percentage of voting power of the entity's share capital an employee is expteced to hold at the time of an ISO grant to him to have him subjected to special contractual term and exercise price of that grant.

+ References

No definition available.

+ Details

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- Definition

Percentage of share-based awards granted generally vest after the first year of service.

+ References

No definition available.

+ Details

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- Definition

Remaining vesting period after the first year of service expected to be rendered in order to acquire relevant share based awards.

+ References

No definition available.

+ Details

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- Definition

The total fair value of options for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to exercise the options in accordance with the terms of the arrangement.

+ References

No definition available.

+ Details

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- Definition

The contractual term of share-based awards granted.

+ References

No definition available.

+ Details

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

+ Details

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- Definition

Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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SHARE-BASED AWARDS PLAN - Additional Information (Detail) In Millions, except Share data, unless otherwise specified	12 Months Ended					12 Months Ended		12 Months Ended													12 Months Ended				6 Months Ended
	Dec. 31, 2011	Dec. 31, 2011 Baidu, Inc. Share Option Except ISO to More Than Ten Percent Voting Power Employee Under 2008 Plan Year	Dec. 31, 2011 Baidu, Inc. ISO to More Than Ten Percent Voting Power Employee Under 2008 Plan Year	Dec. 31, 2011 Baidu, Inc. ISO to More Than Ten Percent Voting Power Employee Under 2008 Plan Minimum	Dec. 31, 2011 Baidu, Inc. 2000 Plan	Dec. 31, 2011 Baidu, Inc. Share Option Under 2000 Plan	Dec. 31, 2011 Baidu, Inc. 2008 Plan	Dec. 31, 2011 Baidu, Inc. Restricted Stock USD ($) Year	Dec. 31, 2011 Baidu, Inc. Restricted Stock CNY	Dec. 31, 2010 Baidu, Inc. Restricted Stock CNY	Dec. 31, 2009 Baidu, Inc. Restricted Stock CNY	Dec. 31, 2011 Baidu, Inc. Restricted Stock Maximum	Dec. 31, 2011 Baidu, Inc. Restricted Stock Minimum	Dec. 31, 2011 Baidu, Inc. Stock Options USD ($) Year	Dec. 31, 2011 Baidu, Inc. Stock Options CNY	Dec. 31, 2010 Baidu, Inc. Stock Options USD ($)	Dec. 31, 2010 Baidu, Inc. Stock Options CNY	Dec. 31, 2009 Baidu, Inc. Stock Options USD ($)	Dec. 31, 2009 Baidu, Inc. Stock Options CNY	Dec. 31, 2011 Qunar 2007 Plan	Dec. 31, 2011 Qunar 2007 Plan Maximum Year	Dec. 31, 2011 Qunar 2007 Plan Minimum	Dec. 31, 2011 Qunar Stock Options USD ($) Year	Dec. 31, 2011 Qunar Stock Options CNY Year	Dec. 31, 2011 Qunar Stock Option USD ($)	Dec. 31, 2011 Qunar Stock Option CNY	Dec. 31, 2011 Qunar Stock Incentive Plan 2007 After Amended
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reserved ordinary shares for issuance under share-based awards plan					5,040,000		3,428,777													9,600,140							26,060,000
Percentage of share-based awards granted generally vest after the first year of service						25.00%
Remaining vesting period						36 months
Maximum contractual term of share-based awards granted		10	5																		10
Minimum percentage of voting power of the entity's share capital	10.00%
Percentage of the fair market value of the entity's ordinary shares				110.00%																		100.00%
Shares vesting term (in years)												4 years	2 years								4 years	2 years
Total intrinsic value of options exercised														$ 43.83	275.86		263.97		340.13
Unrecognized share-based compensation cost								52.18	328.42					8.43	53.09								6.02	37.91
A weighted-average vesting period over which the deferred cost is expected to be recognized (in years)								2.89	2.89					2.53	2.53								2.72	2.72
The weighted-average grant-date fair value of options granted during respective years														$ 432.68		$ 279.69		$ 94.10
Total fair value of shares vested during respective years, restricted shares								31.58	198.77	237.71	201.83
Total fair value of shares vested during respective years, options																									$ 0.79	5.02