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Deferred Policy Acquisition Costs - Progression of deferred policy acquisition costs (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward] |  |  |  |
Deferred policy acquisition costs and present value of future profits, beginning balance |  | $ 1,682 | $ 1,216 | $ 1,239
Deferred policy acquisition costs and present value of future profits, additions |  | 952 | 940 | 817
Deferred policy acquisition costs and present value of future profits, periodic amortization |  | (860) | (908) | (744)
Deferred policy acquisition costs and present value of future profits, annuity unlocking |  | (77) | 29 | 41
Deferred policy acquisition costs and present value of future profits, change included in realized gains |  | 9 | 15 | 10
Deferred policy acquisition costs and present value of future profits, foreign currency translation |  | 0 | (2) | 0
Deferred policy acquisition costs and present value of future profits, other |  |  |  | 10
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | (669) | 392 | (157)
Deferred policy acquisition costs and present value of future profits, ending balance |  | 1,037 | 1,682 | 1,216
Property and casualty insurance |  |  |  |
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] |  |  |  |
Deferred policy acquisition costs, beginning balance |  | 299 | 270 | 238
Deferred policy acquisition costs, additions |  | 744 | 675 | 588
Deferred policy acquisition costs, periodic amortization |  | (721) | (644) | (556)
Deferred policy acquisition costs, foreign currency translation |  | 0 | (2) | 0
Deferred policy acquisition costs, ending balance |  | 322 | 299 | 270
Annuity and Other |  |  |  |
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] |  |  |  |
Deferred policy acquisition costs, beginning balance |  | 1,285 | 1,217 | 1,110
Deferred policy acquisition costs, additions |  | 206 | 263 | 225
Deferred policy acquisition costs, periodic amortization |  | (120) | (238) | (161)
Deferred policy acquisition costs, annuity unlocking |  | (76) | 29 | 34
Deferred policy acquisition costs, change included in realized gains |  | 8 | 14 | 9
Deferred policy acquisition costs, ending balance |  | 1,303 | 1,285 | 1,217
Movement in Deferred Sales Inducements [Roll Forward] |  |  |  |
Deferred sales inducements, beginning balance |  | 86 | 102 | 110
Deferred sales inducements, additions |  | 2 | 2 | 4
Deferred sales inducements, periodic amortization |  | (13) | (19) | (19)
Deferred sales inducements, annuity unlocking |  | (1) | 0 | 6
Deferred sales inducements, change included in realized gains |  | 1 | 1 | 1
Deferred sales inducements, ending balance |  | 75 | 86 | 102
Movement in Present Value of Future Insurance Profits [Roll Forward] |  |  |  |
Present value of future profits, beginning balance |  | 42 | 49 | 46
Present value of future profits, periodic amortization |  | (6) | (7) | (8)
Present value of future profits, annuity unlocking |  | 0 | 0 | 1
Present value of future profits, other |  |  |  | 10
Present value of future profits, ending balance |  | 36 | 42 | 49
Movement in Unrealized Gains (Losses) Related to Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward] |  |  |  |
Unrealized investment gains (losses), beginning balance | [1] | (30) | (422) | (265)
Unrealized investment gains (losses), change in unrealized | [1] | (669) | 392 | (157)
Unrealized investment gains (losses), ending balance | [1] | (699) | (30) | (422)
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward] |  |  |  |
Deferred policy acquisition costs and present value of future profits, beginning balance |  | 1,383 | 946 | 1,001
Deferred policy acquisition costs and present value of future profits, additions |  | 208 | 265 | 229
Deferred policy acquisition costs and present value of future profits, periodic amortization |  | (139) | (264) | (188)
Deferred policy acquisition costs and present value of future profits, annuity unlocking |  | (77) | 29 | 41
Deferred policy acquisition costs and present value of future profits, change included in realized gains |  | 9 | 15 | 10
Deferred policy acquisition costs and present value of future profits, other |  |  |  | 10
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | (669) | 392 | (157)
Deferred policy acquisition costs and present value of future profits, ending balance |  | 715 | 1,383 | 946
Excluding Unrealized Gains | Annuity and Other |  |  |  |
Movement Analysis of Deferred Policy Acquisition Costs and Present Value of Future Profits [Roll Forward] |  |  |  |
Deferred policy acquisition costs and present value of future profits, beginning balance |  | 1,413 | 1,368 | 1,266
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | 0 | 0 | 0
Deferred policy acquisition costs and present value of future profits, ending balance |  | $ 1,414 | $ 1,413 | $ 1,368
[1] | Adjustments to DPAC related to net unrealized gains/losses on securities and cash flow hedges.

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