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Deferred Policy Acquisition Costs - Progression of deferred policy acquisition costs (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
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 |  | $ 1,447 | $ 1,417 | $ 1,682 | $ 1,216
Deferred policy acquisition costs and present value of future profits, additions |  | 250 | 252 | 502 | 471
Deferred policy acquisition costs and present value of future profits, periodic amortization |  | (200) | (233) | (395) | (463)
Deferred policy acquisition costs and present value of future profits, annuity unlocking |  |  | 29 |  | 29
Deferred policy acquisition costs and present value of future profits, change included in realized gains |  | 1 | 3 | 3 | 6
Deferred policy acquisition costs and present value of future profits, foreign currency translation |  | (1) | (2) | 0 | (1)
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | (294) | 116 | (589) | 324
Deferred policy acquisition costs and present value of future profits, ending balance |  | 1,203 | 1,582 | 1,203 | 1,582
P&C |  |  |  |  |
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] |  |  |  |  |
Deferred policy acquisition costs, beginning balance |  | 312 | 279 | 299 | 270
Deferred policy acquisition costs, additions |  | 194 | 181 | 381 | 343
Deferred policy acquisition costs, periodic amortization |  | (175) | (160) | (350) | (314)
Deferred policy acquisition costs, foreign currency translation |  | (1) | (2) | 0 | (1)
Deferred policy acquisition costs, ending balance |  | 330 | 298 | 330 | 298
Annuity and Other |  |  |  |  |
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] |  |  |  |  |
Deferred policy acquisition costs, beginning balance |  | 1,336 | 1,208 | 1,285 | 1,217
Deferred policy acquisition costs, additions |  | 56 | 70 | 120 | 127
Deferred policy acquisition costs, periodic amortization |  | (19) | (66) | (34) | (135)
Deferred policy acquisition costs, annuity unlocking |  |  | 28 |  | 28
Deferred policy acquisition costs, change included in realized gains |  | 0 | 3 | 2 | 6
Deferred policy acquisition costs, ending balance |  | 1,373 | 1,243 | 1,373 | 1,243
Movement in Deferred Sales Inducements [Roll Forward] |  |  |  |  |
Deferred sales inducements, beginning balance |  | 84 | 97 | 86 | 102
Deferred sales inducements, additions |  | 0 | 1 | 1 | 1
Deferred sales inducements, periodic amortization |  | (4) | (5) | (7) | (10)
Deferred sales inducements, annuity unlocking |  |  | 1 |  | 1
Deferred sales inducements, change included in realized gains |  | 1 | 0 | 1 | 0
Deferred sales inducements, ending balance |  | 81 | 94 | 81 | 94
Movement in Present Value of Future Insurance Profits [Roll Forward] |  |  |  |  |
Present value of future profits, beginning balance |  | 40 | 47 | 42 | 49
Present value of future profits, periodic amortization |  | (2) | (2) | (4) | (4)
Present value of future profits, annuity unlocking |  |  | 0 |  | 0
Present value of future profits, ending balance |  | 38 | 45 | 38 | 45
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] | (325) | (214) | (30) | (422)
Unrealized investment gains (losses), change in unrealized | [1] | (294) | 116 | (589) | 324
Unrealized investment gains (losses), ending balance | [1] | (619) | (98) | (619) | (98)
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 |  | 1,135 | 1,138 | 1,383 | 946
Deferred policy acquisition costs and present value of future profits, additions |  | 56 | 71 | 121 | 128
Deferred policy acquisition costs and present value of future profits, periodic amortization |  | (25) | (73) | (45) | (149)
Deferred policy acquisition costs and present value of future profits, annuity unlocking |  |  | 29 |  | 29
Deferred policy acquisition costs and present value of future profits, change included in realized gains |  | 1 | 3 | 3 | 6
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | (294) | 116 | (589) | 324
Deferred policy acquisition costs and present value of future profits, ending balance |  | 873 | 1,284 | 873 | 1,284
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 |  | 1,460 | 1,352 | 1,413 | 1,368
Deferred policy acquisition costs and present value of future profits, change in unrealized |  | 0 | 0 | 0 | 0
Deferred policy acquisition costs and present value of future profits, ending balance |  | $ 1,492 | $ 1,382 | $ 1,492 | $ 1,382
[1] | Adjustments to DPAC related to net unrealized gains/losses on securities and cash flow hedges.

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