Accumulated other comprehensive income (Details) - CHF (SFr) SFr in Millions	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	SFr (15,067)
Balance at end of period	(19,900)
Gains/(losses) on cash flow hedges
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(1,317)	SFr (95)
Increase/(decrease)	289	(727)
Reclassification adjustments, included in net income	(82)	(121)
Total increase/(decrease)	207	(848)
Balance at end of period	(1,110)	(943)
Cumulative translation adjustments
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(17,020)	(16,760)
Increase/(decrease)	(1,072)	934
Reclassification adjustments, included in net income	59	0
Total increase/(decrease)	(1,013)	934
Balance at end of period	(18,033)	(15,826)
Unrealized gains/(losses) on securities
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(13)	13
Increase/(decrease)	1	(6)
Reclassification adjustments, included in net income	0	0
Total increase/(decrease)	1	(6)
Balance at end of period	(12)	7
Actuarial gains/(losses)
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(582)	(429)
Increase/(decrease)	(47)	0
Reclassification adjustments, included in net income	3	4
Total increase/(decrease)	(44)	4
Balance at end of period	(626)	(425)
Net prior service credit/ (cost)
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(9)	(6)
Increase/(decrease)	0	(1)
Reclassification adjustments, included in net income	1	1
Total increase/(decrease)	1	0
Balance at end of period	(8)	(6)
Accumulated Gains (Losses) On Liabilities Related To Credit Risk
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	3,874	(2,082)
Increase/(decrease)	3,746	3,516
Reclassification adjustments, included in net income	(7,731)	17
Reclassification from accumulated other comprehensive income current period impact write down additional tier 1 capital income tax expense benefit	1,440
Reclassification from accumulated other comprehensive income, current period, write down additional tier 1 capital gross of tax	(9,048)
Total increase/(decrease)	(3,985)	3,533
Balance at end of period	(111)	1,451
Accumulated other comprehensive income
Increase (Decrease) in Accumulated other Comprehensive Income
Balance at beginning of period	(15,067)	(19,359)
Increase/(decrease)	2,917	3,716
Reclassification adjustments, included in net income	(7,750)	(99)
Total increase/(decrease)	(4,833)	3,617
Balance at end of period	SFr (19,900)	SFr (15,742)

Tax impact of the additional tier 1 capital write-down

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- Definition

Impact of the additional tier 1 capital write-down, gross of tax

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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