Unaudited Consolidated Balance Sheets (Parenthetical) - USD ($)	Jun. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Available-for-sale debt securities, amortized cost	$ 8,384,025,000	$ 8,587,179,000
Held-to-maturity debt securities, fair value	$ 451,747,000	$ 0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock issued (in shares)	179,253,801	186,305,332
Common stock outstanding (in shares)	179,253,801	186,305,332

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Amortized cost excluding accrued interest, before allowance for credit loss, 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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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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