Condensed Financial Information of the Parent Company - Condensed Statements of Comprehensive Income (Detail)
¥ in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2017
CNY (¥)
Dec. 31, 2017
USD ($)
Dec. 31, 2016
CNY (¥)
Dec. 31, 2015
CNY (¥)
Operating expenses:        
General and administrative expenses ¥ (281,951) $ (43,335) ¥ (306,794) ¥ (193,655)
Operating losses 2,043,253 314,042 1,153,369 1,199,807
Interest income 220,282 33,857 88,168 63,218
Income before income taxes 2,261,541 347,592 1,248,852 1,276,191
Income tax expense 267,082 41,050 32,629 285,542
Net income attributable to Autohome Inc. 2,001,619 307,642 1,227,914 990,649
Other comprehensive income/(loss), net of tax of nil        
Foreign currency translation adjustments (55,055) (8,462) 62,256 56,821
Comprehensive income attributable to Autohome Inc. 1,946,564 299,180 1,290,170 1,047,470
Parent Company [Member]        
Operating expenses:        
General and administrative expenses (13,334) (2,049) (20,533) (24,235)
Operating losses (13,334) (2,049) (20,533) (24,235)
Interest income 13,441 2,066 7,492 11,526
Share of income of subsidiaries and VIEs 2,001,512 307,625 1,240,955 1,003,358
Income before income taxes 2,001,619 307,642 1,227,914 990,649
Income tax expense 0 0 0 0
Net income attributable to Autohome Inc. 2,001,619 307,642 1,227,914 990,649
Other comprehensive income/(loss), net of tax of nil        
Foreign currency translation adjustments (55,055) (8,462) 62,256 56,821
Comprehensive income attributable to Autohome Inc. ¥ 1,946,564 $ 299,180 ¥ 1,290,170 ¥ 1,047,470