Derivatives and hedging activities (Details 6) - CHF (SFr) SFr in Billions	Jun. 30, 2022	Dec. 31, 2021
Investment securities
Hedged items in fair value hedges [Line Items]
Hedged Asset, Fair Value Hedge	SFr 0.7	SFr 0.8
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(0.1)	0.0
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	0.0	0.0
Long-term debt
Hedged items in fair value hedges [Line Items]
Hedged Liability, Fair Value Hedge	67.1	69.4
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	(2.3)	(0.2)
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	(1.7)	0.8
Net loans
Hedged items in fair value hedges [Line Items]
Hedged Asset, Fair Value Hedge	16.5	16.6
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(1.5)	(0.2)
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	(0.1)	0.2
Bank \| Investment securities
Hedged items in fair value hedges [Line Items]
Hedged Asset, Fair Value Hedge	0.7	0.8
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(0.1)	0.0
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	0.0	0.0
Bank \| Long-term debt
Hedged items in fair value hedges [Line Items]
Hedged Liability, Fair Value Hedge	63.4	65.6
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	(2.0)	(0.1)
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	(1.4)	0.8
Bank \| Net loans
Hedged items in fair value hedges [Line Items]
Hedged Asset, Fair Value Hedge	16.5	16.6
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	(1.5)	(0.2)
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease)	SFr (0.1)	SFr 0.2

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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- Definition

Amount of asset hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge.

+ References

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Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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