XML 77 R56.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Investments - Short-term Investments - Additional information (Detail) ¥ in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2017 CNY (¥) | Dec. 31, 2016 CNY (¥) | Dec. 31, 2015 CNY (¥)
Schedule of Investments [Line Items] |  |  |  |
Investment interest income | $ 485 | ¥ 3,154 | ¥ 2,342 | ¥ 2,362
Short-term Investments |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment interest income | $ 455 | ¥ 3,000 | ¥ 2,300 | ¥ 2,200
Short-term Investments | Maximum |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Short-term held-to-maturity debt investments maturity | 1 year | 1 year |  |
Short-term available-for-sale debt investments maturity | 1 year | 1 year |  |

X
- Definition The maturity term of available-for-sale investments. + References No definition available. + Details
Name: | bidu_AvailableForSaleInvestmentMaturityTerm
Namespace Prefix: | bidu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maturity term of held-to-maturity debt investments. + References No definition available. + Details
Name: | bidu_HeldToMaturitySecuritiesMaturityTerm
Namespace Prefix: | bidu_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_InvestmentIncomeInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_ShortTermInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |