Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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AOCI - Significant reclassification adjustments (Details 3) - CHF (SFr) SFr in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification adjustments, included in net income
Income tax expense/(benefit)	SFr 1,361	SFr 2,741	SFr 441
Gains/(losses) on cash flow hedges
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	114	33	(8)
Cumulative translation adjustments
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	19	30	79
Unrealized gains/(losses) on securities
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	(7)	0	0
Accumulated other comprehensive income
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	385	332	352
Net prior service credit/ (cost)
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	(109)	(121)	(106)
Net prior service credit/ (cost) \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income, before tax	(138)	(153)	(134)
Income tax expense/(benefit)	29	32	28
Actuarial gains/(losses)
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	319	358	387
Actuarial gains/(losses) \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income, before tax	396	444	513
Income tax expense/(benefit)	(77)	(86)	(126)
Credit Suisse (Gibraltar) Limited \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases			59
AJP Cayman Ltd [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases			17
Credit Suisse Monaco SAM [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases		23
Credit Suisse Securities Johannesburg Proprietary Limited [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases	21
Bank
Reclassification adjustments, included in net income
Income tax expense/(benefit)	1,134	2,781	400
Bank \| Gains/(losses) on cash flow hedges
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	108	26	(16)
Bank \| Cumulative translation adjustments
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	19	30	72
Bank \| Unrealized gains/(losses) on securities
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	(7)	0	0
Bank \| Accumulated other comprehensive income
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	217	149	135
Bank \| Net prior service credit/ (cost)
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	0	0	0
Bank \| Actuarial gains/(losses)
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income	49	61	79
Bank \| Actuarial gains/(losses) \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Reclassification adjustments, included in net income, before tax	55	68	123
Income tax expense/(benefit)	(6)	(7)	(44)
Bank \| Credit Suisse (Gibraltar) Limited \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases			59
Bank \| AJP Cayman Ltd [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases			SFr 17
Bank \| Credit Suisse Monaco SAM [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases		SFr 23
Bank \| Credit Suisse Securities Johannesburg Proprietary Limited [Member] \| Cumulative translation adjustments \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification adjustments, included in net income
Net releases	SFr 21