Quarterly report pursuant to Section 13 or 15(d)

Document And Entity Information

Document And Entity Information - shares
6 Months Ended
Jun. 30, 2020
Aug. 17, 2020
Document Information Line Items    
Trading Symbol PME  
Document Type 10-Q  
Current Fiscal Year End Date --12-31  
Entity Common Stock, Shares Outstanding   79,055,053
Amendment Flag false  
Entity Central Index Key 0001517130  
Entity Current Reporting Status Yes  
Entity Filer Category Accelerated Filer  
Document Period End Date Jun. 30, 2020  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q2  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Document Quarterly Report true  
Document Transition Report false  
Entity File Number 001-35192  
Entity Incorporation, State or Country Code E9  
Entity Tax Identification Number 00-0000000  
Entity Address, Address Line One 18-19/F  
Entity Address, Address Line Two Zhongshan Building A  
Entity Address, Address Line Three No. 154 Hudong Road  
Entity Address, City or Town Fuzhou  
Entity Address, Country CN  
Entity Address, Postal Zip Code 350001  
City Area Code (86)  
Local Phone Number 591-8727-1266  
Title of 12(b) Security Ordinary Shares, $0.001 par value  
Security Exchange Name NASDAQ  
Entity Interactive Data Current Yes