Securities borrowed, lent and subject to repurchase agreements (Details) (CHF) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Securities borrowed or purchased under agreements to resell (CHF million)
Central bank funds sold and securities purchased under resale agreements	172,184	148,962
Deposits paid for securities borrowed	64,779	71,481
Central bank funds sold, securities purchased under resale agreements and securities borrowing transactions, total	236,963	220,443
Securities lent or sold under agreements to repurchase (CHF million)
Central bank funds purchased and securities sold under repurchase agreements	161,220	147,878
Deposits received for securities lent	15,339	20,516
Central bank funds purchased, securities sold under repurchase agreements and securities lending transactions, total	176,559	168,394

Total carrying value of federal funds purchased and carrying value of securities sold under repurchase agreements and deposits received for securities loaned as of the reporting date. Entities may present this total in the notes to consolidated financial statements.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 4

-Section 08

-Paragraph m

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

-Publisher FASB

-Name Accounting Standards Codification

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Total carrying value of federal funds sold, securities purchased under agreements to resell, and deposits paid for securities borrowed as of the reporting date. Entities may present this total in the notes to consolidated financial statements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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

-Publisher FASB

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-Topic 235

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- Definition

This is the amount of cash advanced as security in return for borrowing securities from another party.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 9

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- Definition

The amount of cash received as security in return for loaning securities to another party.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

The amount shown on the books that a bank with insufficient reserves borrows, at the federal funds rate, from another bank to meet its reserve requirements and the amount of securities that an institution sells and agrees to repurchase at a specified date for a specified price, net of any reductions or offsets.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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Includes: (1) the amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements (Federal Funds Sold) and (2) the dollar amount outstanding of funds lent in the form of security resale agreements regardless of maturity, if the agreement requires the bank to resell the identical security purchased or a security that meets the definition of substantially the same in the case of a dollar roll. Also include purchases of participations in pools of securities, regardless of maturity (Securities Purchased Under Agreements to Re-sell).

+ References

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

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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