Subsequent Event (Details) - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Aug. 03, 2018	Aug. 02, 2018
Additional shares issued on IPO [Member]
Subsequent Event [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	1,532,250
Proceeds from Issuance Initial Public Offering	$ 167.4
IPO
Subsequent Event [Line Items]
Sale of Stock, Price Per Share		$ 16.00
Common Stock, Number of Shares Owned	62,500,000
Common Stock, Par or Stated Value Per Share		$ 0.001
Sale of Stock, Number of Shares Issued in Transaction	10,215,000
Proceeds from Issuance Initial Public Offering	$ 144.6
IPO \| Minimum
Subsequent Event [Line Items]
Sale of Stock, Percentage of Ownership after Transaction	84.20%
IPO \| Maximum
Subsequent Event [Line Items]
Sale of Stock, Percentage of Ownership after Transaction	86.00%

Common Stock, Number of Shares Owned

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- Definition

Face amount or stated value per share of common stock.

+ References

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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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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