Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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GOODWILL (Details)		12 Months Ended
GOODWILL (Details)	Dec. 31, 2016 CNY (¥)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2016 CNY (¥)
Changes in the carrying amount of goodwill
Balance at beginning of year			¥ 56,015,185,590	¥ 45,690,440,903
Balance at end of period	¥ 56,015,185,590	$ 8,644,859,796	56,246,051,292	56,015,185,590
Skyscanner
Changes in the carrying amount of goodwill
Acquisition				9,583,716,450
Acquisition-decrease			(59,685,731)
Qunar
Changes in the carrying amount of goodwill
Acquisition	¥ 43,600,000,000			582,240,644
Others
Changes in the carrying amount of goodwill
Acquisition of others			¥ 290,551,433	¥ 158,787,593