CONSOLIDATED STATEMENTS OF CASH FLOWS In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 USD ($)	Dec. 31, 2014 CNY	Dec. 31, 2013 CNY	Dec. 31, 2012 CNY
Cash flow from operating activities
Net income	$ 25,313us-gaap_NetIncomeLoss	157,049us-gaap_NetIncomeLoss	106,054us-gaap_NetIncomeLoss	4,243us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided in operating activities:
Depreciation of property and equipment	1,395us-gaap_Depreciation	8,653us-gaap_Depreciation	7,847us-gaap_Depreciation	5,167us-gaap_Depreciation
Amortization of intangible assets	263us-gaap_AmortizationOfIntangibleAssets	1,634us-gaap_AmortizationOfIntangibleAssets	659us-gaap_AmortizationOfIntangibleAssets	353us-gaap_AmortizationOfIntangibleAssets
Deferred tax expense (benefit)	(3,857)us-gaap_DeferredIncomeTaxExpenseBenefit	(23,931)us-gaap_DeferredIncomeTaxExpenseBenefit	(97,133)us-gaap_DeferredIncomeTaxExpenseBenefit	7,145us-gaap_DeferredIncomeTaxExpenseBenefit
Share-based compensation	14,493us-gaap_ShareBasedCompensation	89,922us-gaap_ShareBasedCompensation	7,561us-gaap_ShareBasedCompensation	13,704us-gaap_ShareBasedCompensation
Losses(gain) on disposal of property and equipment		(2)us-gaap_GainLossOnDispositionOfAssets	518us-gaap_GainLossOnDispositionOfAssets	904us-gaap_GainLossOnDispositionOfAssets
Write-off of deferred offering expenses	522	3,241		6,404
Interest expense relating to convertible note			3,933us-gaap_InterestExpenseDebt
Changes in fair value of the derivative component of the convertible note			26,809
Changes in fair value of the structured deposit	181us-gaap_UnrealizedGainLossOnInvestments	1,124us-gaap_UnrealizedGainLossOnInvestments
Reimbursement of American Depositary Receipt ("ADR") program related expenses	(427)	(2,648)
Changes in operating assets and liabilities:
Accounts receivable	(1,922)	(11,923)	(39,585)	12,545
Accounts receivable due from employees			225	5,788
Prepayments and other current assets	(6,852)	(42,511)	(25,616)	25,662
Deposits	(666)	(4,132)	(476)	2,286
Accrued expenses and other current liabilities	6,097	37,831	22,876	511
Accrued payroll and welfare payable	2,840	17,622	2,604	(1,849)
Amount due to a related party			(8,520)
Long-term payables	2,237	13,881	18,461	8,257
Income tax payable	764us-gaap_IncreaseDecreaseInIncomeTaxes	4,743us-gaap_IncreaseDecreaseInIncomeTaxes	2,953us-gaap_IncreaseDecreaseInIncomeTaxes	1,379us-gaap_IncreaseDecreaseInIncomeTaxes
Net cash generated from operating activities	40,381	250,553	29,170	92,499
Cash flows from investing activities
Acquisition of property and equipment	(2,493)	(15,469)	(9,111)	(29,840)
Acquisition of intangible assets	(277)	(1,719)	(416)	(2,247)
Acquisition of other non-current assets	(3,886)	(24,114)	(2,738)
Restricted cash	400	2,481	(3,941)	(11,209)
Short-term investments	(11,492)	(71,306)		4,000
Time deposits	(46,035)	(285,626)	(121,085)
Change in amounts due from related parties			188,242	(85,616)
Proceeds from disposal of property and equipment	1	9	1,014	43
Net cash generated from (used in) investing activities	(63,782)	(395,744)	51,965	(124,869)
Cash flows from financing activities
Proceeds from short-term bank borrowings	161us-gaap_ProceedsFromShortTermDebt	1,000us-gaap_ProceedsFromShortTermDebt	201,290us-gaap_ProceedsFromShortTermDebt
Repayment of short-term bank borrowings	(2,224)us-gaap_RepaymentsOfShortTermDebt	(13,802)us-gaap_RepaymentsOfShortTermDebt	(188,488)us-gaap_RepaymentsOfShortTermDebt
Restricted cash	9,108	56,512	(56,512)
Proceeds from the issuance of the convertible note			122,584
Proceeds from the exercise of share options	7,863	48,788	3,263
Proceeds from the private placement			91,994
Proceeds from the issuance of ordinary shares				43,006
Proceeds from the initial public offering ("IPO"), net of issuance costs			456,835
Repurchase of ordinary shares				(39,460)
Payment of dividends			(194,526)us-gaap_PaymentsOfDividends
Reimbursement of ADR program related expenses	509	3,161
Payment for public offering expenses	(1,730)us-gaap_PaymentsOfStockIssuanceCosts	(10,737)us-gaap_PaymentsOfStockIssuanceCosts		(3,551)us-gaap_PaymentsOfStockIssuanceCosts
Net cash (used in) generated from financing activities	13,687	84,922	436,440	(5)
Effect of exchange rate changes on cash and cash equivalents	243	1,507	(4,812)
Net increase (decrease) in cash and cash equivalents	(9,471)	(58,762)	512,763	(32,375)
Cash and cash equivalents at beginning of the year	87,728	544,318	31,555	63,930
Cash and cash equivalents at end of the year	78,257	485,556	544,318	31,555
Supplemental disclosures of cash flow information:
Income tax paid	(2,552)us-gaap_IncomeTaxesPaid	(15,836)us-gaap_IncomeTaxesPaid	(2,363)us-gaap_IncomeTaxesPaid	(1,920)us-gaap_IncomeTaxesPaid
Interest paid	(57)us-gaap_InterestPaid	(356)us-gaap_InterestPaid	(694)us-gaap_InterestPaid
Interest received	1,703us-gaap_ProceedsFromInterestReceived	10,568us-gaap_ProceedsFromInterestReceived	1,750us-gaap_ProceedsFromInterestReceived	1,132us-gaap_ProceedsFromInterestReceived
Non-cash movements :
Payable to a related party from repurchase of ordinary shares				8,520

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.