Subsequent Events - Additional Information (Details) - Subsequent Event $ / shares in Units, $ in Millions	Aug. 03, 2018 USD ($) $ / shares shares
Subsequent Event [Line Items]
Stock issued during period, shares, new issues \| shares	2,555,555
Public offering price per share \| $ / shares	$ 18.00
Proceeds from issuance initial public offering, after deduction underwriting discounts, commissions \| $	$ 42.5
Payments for underwriting expense \| $	$ 3.5
Underwritten Public Offering
Subsequent Event [Line Items]
Stock issued during period, shares, new issues \| shares	333,333

Cash paid for expenses incurred during underwriting activities (the process to review insurance applications, evaluate risks, accept or reject applications, and determine the premiums to be charged) for insurance companies.

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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- Definition

Number of new stock issued during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
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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.

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