Advertising and promotion (Details) - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Advertising and promotion details
Advertising and promotion costs	$ 1,847	$ 2,541

The total expense recognized in the period for promotion, public relations, and brand or product advertising.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Name:	us-gaap_MarketingAndAdvertisingExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration