The Company (Details)	Jul. 27, 2015 employee $ / shares shares	Jun. 30, 2015 subsidiary
Subsidiary, Sale of Stock [Line Items]
Number of wholly-owned subsidiaries | subsidiary		5
Subsequent event
Subsidiary, Sale of Stock [Line Items]
Number of shares issued to non-management employees	35,934
Number of non-management employees receiving shares | employee	1,700
Subsequent event | IPO and over-allotment
Subsidiary, Sale of Stock [Line Items]
Number of shares sold	38,906,286
Initial public offering share price | $ / shares	$ 20.00
Subsequent event | Over-allotment option
Subsidiary, Sale of Stock [Line Items]
Number of shares sold	5,074,732