Investment securities by type (Details 2) - CHF (SFr) SFr in Millions	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Available-for-sale securities
Amortized cost, before allowance for credit losses, Debt Securities	SFr 851		SFr 1,013
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Gross unrealized gains, Debt securities	0		0
Gross unrealized losses, Debt securities	112		8
Fair value, Debt securities	739	SFr 809	1,005
Debt securities issued by the Swiss federal, cantonal or local government entities
Available-for-sale securities
Amortized cost, before allowance for credit losses, Debt Securities	2		2
Gross unrealized gains, Debt securities	0		0
Gross unrealized losses, Debt securities	0		0
Fair value, Debt securities	2		2
Corporate debt securities
Available-for-sale securities
Amortized cost, before allowance for credit losses, Debt Securities	849		1,011
Gross unrealized gains, Debt securities	0		0
Gross unrealized losses, Debt securities	112		8
Fair value, Debt securities	737		1,003
Bank
Available-for-sale securities
Amortized cost, before allowance for credit losses, Debt Securities	849		1,011
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Gross unrealized gains, Debt securities	0		0
Gross unrealized losses, Debt securities	112		8
Fair value, Debt securities	737		1,003
Bank \| Corporate debt securities
Available-for-sale securities
Amortized cost, before allowance for credit losses, Debt Securities	849		1,011
Gross unrealized gains, Debt securities	0		0
Gross unrealized losses, Debt securities	112		8
Fair value, Debt securities	SFr 737		SFr 1,003

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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