v3.19.1

Nature of Business and Basis of Presentation - Initial Public Offering (Details) - Common Stock - IPO - USD ($) $ / shares in Units, $ in Millions |  | 12 Months Ended
--- | --- | ---
Sep. 28, 2018 | Dec. 31, 2018
Subsidiary, Sale of Stock [Line Items] |  |
Number of shares issued in transaction (in shares) | 2,563,046 |
Sale of stock, price per share (in dollars per share) | $ 12.50 |
Sale of stock, consideration received | $ 19.8 |
Underwriting discount and offering costs | $ (3.2) | $ (3.2)
Parent Company |  |
Subsidiary, Sale of Stock [Line Items] |  |
Number of shares issued in transaction (in shares) | 1,834,310 |
Affiliated Entity | Selling Shareholders |  |
Subsidiary, Sale of Stock [Line Items] |  |
Number of shares issued in transaction (in shares) | 728,736 |

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