TFA - Accounted for as sales - by transaction type (Details 6) - CHF (SFr) SFr in Millions	Dec. 31, 2017	Dec. 31, 2016
Transfer of Financial Assets Accounted for as Sales [Line Items]
Carrying amount derecognized		SFr 277
Gross cash proceeds received for assets derecognized		340
Fair value of transferred assets		374
Gross derivative assets recorded	SFr 145,000	229,500
Gross derivative liabilities recorded	146,700	232,800
Interest rate derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	85,900	137,400
Gross derivative liabilities recorded	81,000	129,300
Foreign exchange derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	29,300	59,300
Gross derivative liabilities recorded	34,800	69,300
Equity/index-related derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	20,900	22,700
Gross derivative liabilities recorded	21,500	24,500
Credit derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	7,500	7,900
Gross derivative liabilities recorded	8,500	8,500
Other products
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	1,400	2,200
Gross derivative liabilities recorded	900	1,200
Sales with longevity swaps
Transfer of Financial Assets Accounted for as Sales [Line Items]
Carrying amount derecognized		277
Gross cash proceeds received for assets derecognized		340
Fair value of transferred assets		374
Derivatives related to Transfers of Assets accounted for as sale
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded		556
Derivatives related to Transfers of Assets accounted for as sale \| Other products
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded		556
Derivatives related to Transfers of Assets accounted for as sale \| Sales with longevity swaps
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded		556
Bank
Transfer of Financial Assets Accounted for as Sales [Line Items]
Carrying amount derecognized		277
Gross cash proceeds received for assets derecognized		340
Fair value of transferred assets		374
Gross derivative assets recorded	145,000	229,500
Gross derivative liabilities recorded	147,000	233,000
Bank \| Interest rate derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	85,900	137,400
Gross derivative liabilities recorded	81,000	129,300
Bank \| Foreign exchange derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	29,300	59,300
Gross derivative liabilities recorded	34,800	69,300
Bank \| Equity/index-related derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	20,900	22,700
Gross derivative liabilities recorded	21,800	24,700
Bank \| Credit derivatives
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	7,500	7,900
Gross derivative liabilities recorded	8,500	8,500
Bank \| Other products
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	1,400	2,200
Gross derivative liabilities recorded	900	1,200
Bank \| Sales with longevity swaps
Transfer of Financial Assets Accounted for as Sales [Line Items]
Carrying amount derecognized		277
Gross cash proceeds received for assets derecognized		340
Fair value of transferred assets		374
Bank \| Derivatives related to Transfers of Assets accounted for as sale
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded		556
Bank \| Derivatives related to Transfers of Assets accounted for as sale \| Other products
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded	SFr 0	556
Bank \| Derivatives related to Transfers of Assets accounted for as sale \| Sales with longevity swaps
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross derivative assets recorded		SFr 556

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

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Amount of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction, at the date of derecognition.

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+ References

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Fair value of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction.

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No definition available.

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