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Parent Company - Condensed Statement of Cash Flows (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Condensed Cash Flow Statements, Captions [Line Items] |  |  |
Net income | $ 739 | $ 124 | $ 389
Equity in earnings (losses) of investees | (28) | 39 | (94)
Net realized investment gains (losses) | 14 | 56 | (15)
Net cash flows provided by (used in) operating activities | 461 | (2,479) | (1,937)
Sales | (4) | 0 | 0
Maturities and paydowns | 746 | 682 | 1,148
Net sales (purchases) of short-term investments with original maturities of less than three months | (872) | 439 | (410)
Net cash flows provided by (used in) investing activities | 286 | 1,740 | 23
Dividends paid | (67) | (64) | (66)
Repurchases of common shares | (199) | (500) | (496)
Other | (19) | (6) | 26
Net cash flows provided by (used in) financing activities | (670) | 612 | 1,960
Increase (decrease) in cash and cash equivalents and restricted cash | 79 | (135) | 44
Cash and cash equivalents and restricted cash at beginning of period | 207 | 342 | 298
Cash and cash equivalents and restricted cash at end of period | 286 | 207 | 342
AG Re | Assured Guaranty LTD |  |  |
Condensed Cash Flow Statements, Captions [Line Items] |  |  |
Dividend from a subsidiary in the form of fixed-maturity securities | 0 | 0 | 46
Assured Guaranty Ltd. (Parent) |  |  |
Condensed Cash Flow Statements, Captions [Line Items] |  |  |
Net income | 739 | 124 | 389
Equity in earnings (losses) of investees | (784) | (170) | (423)
Net realized investment gains (losses) | 1 | 4 | 0
Cash dividends from subsidiaries | 306 | 437 | 539
Other | 36 | 32 | 22
Net cash flows provided by (used in) operating activities | 298 | 427 | 527
Sales | 4 | 52 | 0
Maturities and paydowns | 0 | 5 | 4
Net sales (purchases) of short-term investments with original maturities of less than three months | (18) | 92 | 41
Net cash flows provided by (used in) investing activities | (14) | 149 | 45
Dividends paid | (67) | (64) | (66)
Repurchases of common shares | (199) | (500) | (496)
Other | (18) | (12) | (10)
Net cash flows provided by (used in) financing activities | (284) | (576) | (572)
Increase (decrease) in cash and cash equivalents and restricted cash | 0 | 0 | 0
Cash and cash equivalents and restricted cash at beginning of period | 0 | 0 | 0
Cash and cash equivalents and restricted cash at end of period | $ 0 | $ 0 | $ 0

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