Represents the total number seats of Board of directors

No definition available.

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Data Type:	xbrli:integerItemType
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- Definition

Represents the number of seats of board of directors allocated.

+ References

No definition available.

+ Details

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- Definition

Represents the cumulative number of shares of stock acquired by the reporting entity as of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

Percentage of investee's equity interest owned by the investor.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Purchase of Shares, Price per Share

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Purchase of Shares, Shares Purchased

+ References

No definition available.

+ Details

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

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Name:	us-gaap_PaymentsToAcquireInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	invest_InvestmentIssuerAxis=ctrp_HantingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ctrp_PurchaseOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ctrp_PurchaseOfStockAxis=ctrp_ShareholdersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ctrp_PurchaseOfStockAxis=us-gaap_IPOMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=ctrp_AdsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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INVESTMENTS (Details 3) $ / shares in Units, ¥ in Millions, $ in Millions			1 Months Ended		9 Months Ended
	Mar. 31, 2010 USD ($) item $ / shares shares	Mar. 31, 2010 CNY (¥)	Apr. 30, 2014 CNY (¥)	Mar. 31, 2010 item $ / shares shares	Sep. 30, 2015 CNY (¥)	Sep. 30, 2015 USD ($) $ / shares	Sep. 30, 2015 CNY (¥)
Hanting
Investment transaction disclosures
Purchase of shares, cost of share aggregate	$ 67.5	¥ 461
Purchase of shares, number aggregate	22,049,446			22,049,446
Percentage of equity interest purchased aggregate	9.00%			9.00%
Total number of seats \| item	7			7
Number of seats \| item	1			1
Fair value of available-for-sale investment						$ 134.0	¥ 852
Increase in fair value of the investment credited to other comprehensive income \| ¥					¥ 423
Hanting \| Ordinary shares \| Private placement
Investment transaction disclosures
Purchase of shares, shares purchased				7,202,482
Hanting \| Ordinary shares \| Shareholders
Investment transaction disclosures
Purchase of shares, shares purchased				11,646,964
Hanting \| Ordinary shares \| IPO
Investment transaction disclosures
Purchase of shares, shares purchased				3,200,000
Purchase of shares, price per share \| $ / shares	$ 3.0625			$ 3.0625
Hanting \| ADS
Investment transaction disclosures
Purchase of shares, number aggregate	3,200,000			3,200,000
Closing price of ADS (in dollars per share) \| $ / shares						$ 24.33
Hanting \| ADS \| IPO
Investment transaction disclosures
Purchase of shares, shares purchased				800,000
Purchase of shares, price per share \| $ / shares	$ 12.25			$ 12.25
LY.com
Investment transaction disclosures
Purchase of shares, cost of share aggregate \| ¥			¥ 1,400