Represents the prepayment speed rate assumed used for projecting payments over the life of a residential mortgage loan.

No definition available.

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- Definition

Represents the constant prepayment rate assumed using a 100 percent prepayment assumption.

+ References

No definition available.

+ Details

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- Definition

Represents the prepayment rate per annum of the outstanding principal balance of mortgage loans in the first month assuming 100 percent prepayment.

+ References

No definition available.

+ Details

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- Definition

Represents the prepayment rate per annum of the outstanding principal balance of mortgage loans after the first month assuming 100 percent prepayment.

+ References

No definition available.

+ Details

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-3

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- Definition

Rate at which principal will not be repaid on securitized financial assets, including for example, but not limited to, expected static pool losses for initial fair value measurement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-3

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
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- Definition

Estimated rate of prepayment of principal on financial assets for initial fair value measurement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-3

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- Definition

Weighted average life of securitized assets for initial fair value measurement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Represents the initial fair value recorded for assets received on transfer of financial assets in a securitization, asset-backed financing arrangement, or a similar transfer which transaction is recognized as a sale of the transferred financial assets.

+ References

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TFA - Key economic assumptions at time of transfer (Details 3) - CHF (SFr) SFr in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer	SFr 0
Prepayment speed rate assumed used for projecting payments over the life of a residential mortgage loan (as a percent)	100.00%
Prepayment rate per annum of the outstanding principal balance of mortgage loans in the first month assuming 100% prepayment (as a percent)	0.20%
Prepayment rate per annum of the outstanding principal balance of mortgage loans after the first month assuming 100% prepayment (as a percent)	0.20%
Constant prepayment rate assumed using a 100% prepayment assumption (as a percent)	6.00%
CMBS
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		SFr 486	SFr 196
Weighted-average life, in years		4 years 1 month 6 days	5 years 2 months 12 days
CMBS \| Minimum
Key economic assumptions used in measuring fair value at time of transfer
Cash flow discount rate (rate per annum), in % (as a percent)		3.50%	1.80%
Expected credit losses (rate per annum), in % (as a percent)		2.70%	0.90%
CMBS \| Maximum
Key economic assumptions used in measuring fair value at time of transfer
Cash flow discount rate (rate per annum), in % (as a percent)		15.70%	5.00%
Expected credit losses (rate per annum), in % (as a percent)		5.60%	4.30%
CMBS \| Level 2
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		SFr 415	SFr 170
CMBS \| Level 3
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		71	26
RMBS
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		SFr 847	SFr 2,594
Weighted-average life, in years		9 years 6 months	5 years 3 months 18 days
RMBS \| Minimum
Key economic assumptions used in measuring fair value at time of transfer
Prepayment speed assumption (rate per annum) in % (as a percent)		5.00%	3.00%
Cash flow discount rate (rate per annum), in % (as a percent)		2.80%	1.00%
Expected credit losses (rate per annum), in % (as a percent)		1.30%	0.10%
RMBS \| Maximum
Key economic assumptions used in measuring fair value at time of transfer
Prepayment speed assumption (rate per annum) in % (as a percent)		22.20%	37.70%
Cash flow discount rate (rate per annum), in % (as a percent)		53.80%	33.40%
Expected credit losses (rate per annum), in % (as a percent)		49.80%	32.50%
RMBS \| Level 2
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		SFr 762	SFr 2,126
RMBS \| Level 3
Key economic assumptions used in measuring fair value at time of transfer
Fair value of beneficial interests at time of transfer		SFr 85	SFr 468