Reflects the amount of loan granted by the related parties.

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Represents the maturity term of the loan receivable, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of payables and accruals classified as other, payable within one year or the normal operating cycle, if longer.

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Face (par) amount of debt instrument at time of issuance.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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Aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due after one year (or one business cycle).

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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No definition available.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

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RELATED PARTY TRANSACTIONS AND BALANCES (Details)						12 Months Ended
RELATED PARTY TRANSACTIONS AND BALANCES (Details)	Oct. 27, 2015 USD ($)	Oct. 27, 2015 CNY (¥)	Oct. 26, 2015 USD ($)	May 04, 2015 CNY (¥)	Mar. 12, 2015 CNY (¥)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2016 CNY (¥)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CNY (¥)	Dec. 31, 2014 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 CNY (¥)	Oct. 26, 2015 CNY (¥)
RELATED PARTY TRANSACTIONS AND BALANCES
Repayment of entrusted loan and interest to related parties							¥ 1,820,911,519
Due from related parties, current							787,603,986				$ 57,448,327	¥ 373,776,048
Due from related parties, non-current							599,913,241				33,560,296	218,353,359
Due to related parties, current							837,421,345				64,322,406	418,500,869
Other payables and accruals							2,849,821,247				$ 783,338,681	5,096,636,473
eLong
RELATED PARTY TRANSACTIONS AND BALANCES
Commissions from related parties						¥ 573,127,860	261,139,916		¥ 7,191,870
Commissions to related parties						243,783,254	85,780,819		9,532,316
Due from related parties, current							132,381,883					152,825,748
Due to related parties, current							506,461,015					273,480,768
Hanting
RELATED PARTY TRANSACTIONS AND BALANCES
Commissions from related parties						76,792,041	44,094,542		17,740,390
Homeinns and BTG
RELATED PARTY TRANSACTIONS AND BALANCES
Commissions from related parties						62,528,564	66,921,837		34,556,539
Baidu
RELATED PARTY TRANSACTIONS AND BALANCES
Loan and interest to related parties	$ 100,000,000	¥ 650,000,000
Repayment of entrusted loan and interest from related parties							652,299,803
Commissions to related parties						80,474,320	96,056,853
Online marketing service from related parties						38,015,114	110,064,311		89,244,042
Repayment of entrusted loan and interest to related parties							1,837,384,234
Term of the loan	12 months	12 months
Interest rate on loan (as a percent)	1.00%	1.00%
Due from related parties, current							408,834,667					118,564,122
Due to related parties, current							293,579,066					58,287,646
Baidu \| Qunar
RELATED PARTY TRANSACTIONS AND BALANCES
Loan and interest to related parties								$ 100,000,000	¥ 650,000,000
Term of the loan								1 year	1 year
Outstanding balance related to business cooperation agreement							409,000,000					119,000,000
Debt instrument term								3 years	3 years
Principal loan amount									¥ 1,100,000,000
Skysea
RELATED PARTY TRANSACTIONS AND BALANCES
Loan and interest to related parties						4,346,586	73,399,675		15,826,363	$ 80,000,000
Interest rate on loan (as a percent)										3.00%
Provision for the loan and receivable												536,000,000
Due from related parties, current							132,035,460
Due from related parties, non-current							599,913,241					195,615,163
Other payables and accruals												367,000,000
LY.com
RELATED PARTY TRANSACTIONS AND BALANCES
Commissions to related parties						¥ 70,208,452	62,150,144		¥ 75,297,659
Due from related parties, current							96,308,665					57,808,027
Others
RELATED PARTY TRANSACTIONS AND BALANCES
Due from related parties, current							18,043,311					44,578,151
Due from related parties, non-current												22,738,196
Due to related parties, current							¥ 37,381,264					¥ 86,732,455
Baidu Times \| Qunar
RELATED PARTY TRANSACTIONS AND BALANCES
Interest rate on loan (as a percent)			4.14%
Loan granted by related parties			$ 99,000,000										¥ 640,000,000
Debt instrument term			12 months
Revolving credit facility agreement \| Qunar
RELATED PARTY TRANSACTIONS AND BALANCES
Drawdowns during the period				¥ 627,000,000	¥ 507,000,000