v3.25.4

Unrealized Losses on Debt Investments (Detail) - USD ($) $ in Millions | Dec. 31, 2025 | Jun. 30, 2025
--- | --- | ---
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | $ 830 | $ 4,560
Less than 12 Months - Unrealized Losses | (9) | (65)
12 Months or Greater - Fair Value | 31,365 | 38,176
12 Months or Greater - Unrealized Losses | (1,137) | (1,560)
Total Fair Value | 32,195 | 42,736
Total Unrealized Losses | (1,146) | (1,625)
U.S. government and agency securities |  |
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | 350 | 2,569
Less than 12 Months - Unrealized Losses | (4) | (51)
12 Months or Greater - Fair Value | 28,600 | 34,608
12 Months or Greater - Unrealized Losses | (1,042) | (1,411)
Total Fair Value | 28,950 | 37,177
Total Unrealized Losses | (1,046) | (1,462)
Foreign government bonds |  |
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | 48 | 43
Less than 12 Months - Unrealized Losses | (3) | (2)
12 Months or Greater - Fair Value | 83 | 106
12 Months or Greater - Unrealized Losses | (3) | (7)
Total Fair Value | 131 | 149
Total Unrealized Losses | (6) | (9)
Mortgage- and asset-backed securities |  |
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | 0 | 841
Less than 12 Months - Unrealized Losses | 0 | (4)
12 Months or Greater - Fair Value | 202 | 189
12 Months or Greater - Unrealized Losses | (21) | (23)
Total Fair Value | 202 | 1,030
Total Unrealized Losses | (21) | (27)
Corporate notes and bonds |  |
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | 432 | 1,107
Less than 12 Months - Unrealized Losses | (2) | (8)
12 Months or Greater - Fair Value | 2,318 | 3,105
12 Months or Greater - Unrealized Losses | (53) | (98)
Total Fair Value | 2,750 | 4,212
Total Unrealized Losses | (55) | (106)
Municipal securities |  |
Unrealized Losses on Investments [Line Items] |  |
Less than 12 Months - Fair Value | 0 | 0
Less than 12 Months - Unrealized Losses | 0 | 0
12 Months or Greater - Fair Value | 162 | 168
12 Months or Greater - Unrealized Losses | (18) | (21)
Total Fair Value | 162 | 168
Total Unrealized Losses | $ (18) | $ (21)

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