PROPERTY, PLANT AND EQUIPMENT, NET
 12 Months Ended
Dec. 31, 2017
PROPERTY, PLANT AND EQUIPMENT, NET [Abstract]  
PROPERTY, PLANT AND EQUIPMENT, NET
9
PROPERTY, PLANT AND EQUIPMENT, NET
 
Property, plant and equipment consist of the following:
 
 
 
As at December 31,
 
 
 
2016
 
2017
 
2017
 
 
 
RMB
 
RMB
 
US$
 
Buildings
 
 
227,196
 
 
230,273
 
 
35,392
 
Medical equipment
 
 
899,281
 
 
668,169
 
 
102,696
 
Electronic and office equipment
 
 
15,804
 
 
16,864
 
 
2,592
 
Motor vehicles
 
 
2,621
 
 
2,361
 
 
363
 
Leasehold improvement and building improvements
 
 
7,277
 
 
14,771
 
 
2,270
 
Construction in progress
 
 
122,635
 
 
329,259
 
 
50,606
 
Total
 
 
1,274,814
 
 
1,261,697
 
 
193,919
 
Less: accumulated depreciation
 
 
(432,884)
 
 
(407,964)
 
 
(62,703)
 
 
 
 
841,930
 
 
853,733
 
 
131,216
 
Impairment charges
 
 
(66,592)
 
 
(60,162)
 
 
(9,246)
 
 
 
 
775,338
 
 
793,571
 
 
121,970
 
 
Depreciation expenses were RMB138,075, RMB117,051 and RMB83,224 (US$12,791) for the years ended December 31, 2015, 2016 and 2017, respectively. Impairment loss of RMB23,125, RMB47,827 and RMB 21,476 (US$3,301) were recognized for the years ended December 31, 2015, 2016 and 2017, respectively. Impairment charges mainly include impairment provided for medical equipment in several low performance centers as well as idle assets.
 
For the years ended December 31, 2015, 2016 and 2017, nil, RMB4,360 and RMB27,906(US$4,289) impairment was written off upon the disposal of medical equipment.
 
As at December31, 2016 and 2017, certain of the Group's property, plant and equipment with a total net book value of RMB111,728 and RMB37,481 (US$5,761) were pledged as collaterals for bank borrowings of RMB78,445 and RMB29,725 (US$4,569), respectively (note17).
 
As at December 31, 2016 and 2017, certain of the Group's construction in progress with a total net book value of nil and RMB206,244 (US$31,699) were pledged to secure other borrowings of nil and RMB280,459 (US$43,105), respectively (note 17) and mandatorily redeemable noncontrolling interest of nil and RMB396,281 (US$60,907) (note 1), respectively.
 
As at December 31, 2016 and 2017, the Group held equipment under operating lease contracts with customers with an original cost of RMB812,207 and RMB519,426 (US$79,834) and accumulated depreciation of RMB354,207 and RMB312,853 (US$48,085), respectively.