Acquisitions and Disposals - Summary of Cash Flows from Discontinued Operations (Detail) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 USD ($)	Dec. 31, 2014 CNY	Dec. 31, 2013 CNY	Dec. 31, 2012 CNY	Dec. 31, 2014 CAH and WHT [Member] USD ($)	Dec. 31, 2014 CAH and WHT [Member] CNY	Dec. 31, 2013 CAH and WHT [Member] CNY	Dec. 31, 2012 CAH and WHT [Member] CNY
Condensed Cash Flow Statements, Captions [Line Items]
Net cash generated from operating activities					$ 9,891	61,372	85,867	93,136
Net cash used in investing activities					(6,998)	(43,420)	(46,461)	(109,126)
Net cash (used in) generated from financing activities					1,713	10,627	(38,153)	(5,467)
Cash acquired in acquisition of CAH in 2012				223,403				28,939
Net increase in cash	31,533us-gaap_CashPeriodIncreaseDecrease	195,649us-gaap_CashPeriodIncreaseDecrease	207,651us-gaap_CashPeriodIncreaseDecrease	(143,696)us-gaap_CashPeriodIncreaseDecrease	4,606	28,579	1,253	7,482
Cash at beginning of year	45,617us-gaap_Cash	283,033us-gaap_Cash	75,382us-gaap_Cash	219,078us-gaap_Cash	1,410	8,748	7,495	13
Cash at end of year	$ 77,150us-gaap_Cash	478,682us-gaap_Cash	283,033us-gaap_Cash	75,382us-gaap_Cash	$ 6,016	37,327	8,748	7,495

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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Amount of increase (decrease) in cash. Cash is the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Includes effect from exchange rate changes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 830

-SubTopic 230

-Section 45

-Paragraph 1

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Amount of cash inflow (outflow) of financing activities of 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount of cash inflow (outflow) of investing activities of discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) of operating activities of discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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-Name Accounting Standards Codification

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