Organization - Schedule of Assets, Liabilities, and Cash Flows of VIEs (Detail) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 USD ($)	Dec. 31, 2014 CNY	Dec. 31, 2013 CNY	Dec. 31, 2012 CNY	Dec. 31, 2014 VIEs [Member] USD ($)	Dec. 31, 2014 VIEs [Member] CNY	Dec. 31, 2013 VIEs [Member] CNY	Dec. 31, 2012 VIEs [Member] CNY
Variable Interest Entity [Line Items]
Current assets	$ 586,785us-gaap_AssetsCurrent	3,640,766us-gaap_AssetsCurrent	1,899,265us-gaap_AssetsCurrent		$ 103,044	639,347	577,529
Non-current assets	263,958us-gaap_AssetsNoncurrent	1,637,749us-gaap_AssetsNoncurrent	1,613,685us-gaap_AssetsNoncurrent		259,852	1,612,276	1,606,709
Total assets	850,743us-gaap_Assets	5,278,515us-gaap_Assets	3,512,950us-gaap_Assets		362,896	2,251,623	2,184,238
Current liabilities	174,173us-gaap_LiabilitiesCurrent	1,080,657us-gaap_LiabilitiesCurrent	789,818us-gaap_LiabilitiesCurrent		80,297	498,209	493,710
Non-current liabilities	85,812us-gaap_LiabilitiesNoncurrent	532,435us-gaap_LiabilitiesNoncurrent	510,768us-gaap_LiabilitiesNoncurrent		4,334	26,889	33,069
Total liabilities	259,985us-gaap_Liabilities	1,613,092us-gaap_Liabilities	1,300,586us-gaap_Liabilities		84,631	525,098	526,779
Net assets					278,265	1,726,525	1,657,459
Net revenues	343,769us-gaap_SalesRevenueNet	2,132,949us-gaap_SalesRevenueNet	1,216,548us-gaap_SalesRevenueNet	732,520us-gaap_SalesRevenueNet	237,469	1,473,401	1,216,410	729,961
Net (loss)/income	120,665us-gaap_NetIncomeLoss	748,680us-gaap_NetIncomeLoss	456,162us-gaap_NetIncomeLoss	212,881us-gaap_NetIncomeLoss	9,244	57,358	28,170	(7,790)
Net cash generated from operating activities	164,998	1,023,743	593,893	279,515	16,504	102,403	29,925	27,633
Net cash used in investing activities	(283,582)	(1,759,517)	(45,943)	(27,734)	(5,443)	(33,773)	(38,100)	(24,865)
Net cash generated from financing activities	$ 104,342	647,396	169,298	(44,910)	$ 0	0	0	0

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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