v3.8.0.1

Summary of significant accounting policies - Practical expedient (Details) | 3 Months Ended
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Mar. 31, 2018
Summary of significant accounting policies |
Practical expedient of financing component | true
Practical expedient of incremental cost | true

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- Definition Indicates (true/false) whether practical expedient is elected not to adjust consideration for effect of financing component when transfer and customer payment of good or service occurs within one year or less. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130569-203045 + Details
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- Definition Indicates (true/false) whether practical expedient is elected to recognize incremental cost of obtaining contract as expense when incurred if amortization period would have been one year or less. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL51790836-203054 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130569-203045 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 25 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68074990&loc=SL49131230-203052 + Details
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