CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale, Amortized Cost	$ 6,166.5	$ 4,586.4
Debt Securities, Held-to-maturity, Fair Value	$ 1,146.4	$ 611.8
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	108,981,341	103,013,290

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Face amount or stated value per share of common stock.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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