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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 02, 2018 | Feb. 28, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Subsequent Event [Line Items] |  |  |  |  |
Proceeds from issuance of common stock, net of offering costs |  |  | $ 103,259 | $ 34,244 | $ 0
Follow Up Offering | Subsequent Event |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Sale of common stock (in shares) |  | 5,500,000 |  |  |
Proceeds from issuance of common stock, net of offering costs |  | $ 118,500 |  |  |
Sale of common stock (in dollars per share) |  | $ 20.00 |  |  |
Over-Allotment Option |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Sale of common stock (in shares) | 675,000 |  |  |  |
Sale of common stock (in dollars per share) | $ 21.25 |  |  |  |
Over-Allotment Option | Subsequent Event |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Sale of common stock (in shares) |  | 825,000 |  |  |
Sale of common stock (in dollars per share) |  | $ 20.00 |  |  |

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- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
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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 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. + Details
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- Details
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- Details
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- Details
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