Pension and other post-retirement benefits (Details 2) (CHF) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined benefit pension plans - Switzerland
Defined benefit plan, Disclosure
PBO	15,661	13,473	14,296
ABO	15,110	13,043
Defined benefit pension plans - Switzerland \| PBO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	15,661	0
ABO	15,110	0
Fair value of plan assets	15,635	0
Defined benefit pension plans - Switzerland \| ABO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	0	0
ABO	0	0
Fair value of plan assets	0	0
Defined benefit pension plans - International
Defined benefit plan, Disclosure
PBO	3,539	2,843	2,773
ABO	3,469	2,785
Defined benefit pension plans - International \| PBO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	1,671	1,334
ABO	1,637	1,307
Fair value of plan assets	1,187	978
Defined benefit pension plans - International \| ABO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	1,655	1,319
ABO	1,627	1,298
Fair value of plan assets	1,173	964
Bank \| Defined benefit pension plans - International
Defined benefit plan, Disclosure
PBO	3,539	2,843	2,773
ABO	3,469	2,785
Bank \| Defined benefit pension plans - International \| PBO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	1,671	1,334
ABO	1,637	1,307
Fair value of plan assets	1,187	978
Bank \| Defined benefit pension plans - International \| ABO exceeds fair value of plan assets
Defined benefit plan, Disclosure
PBO	1,655	1,319
ABO	1,627	1,298
Fair value of plan assets	1,173	964

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=34716465&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920

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