Condensed Consolidated Balance Sheets (Parenthetical) - shares	Sep. 30, 2017	May 15, 2017	Dec. 31, 2016
Common Class A
Common shares issued (in shares)	62,314,850		37,426,008
Common shares outstanding (in shares)	62,314,850		37,426,008
Common Class B
Common shares issued (in shares)	81,463,433	7,142,857	74,320,576
Common shares outstanding (in shares)	81,463,433		74,320,576

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant