v3.19.1

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Sep. 28, 2018 | Dec. 31, 2018
IPO | Common Stock |  |
Underwriting discount and offering costs | $ 3.2 | $ 3.2

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