Consolidated Obligations (Bonds by Callable Feature) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Par value	$ 76,896	$ 83,170
Fair value hedging adjustments	(596)	(1,394)
Other adjustments	(5)	83
Bonds	76,295	81,859
Noncallable
Debt Instrument [Line Items]
Par value	34,722	32,933
Callable
Debt Instrument [Line Items]
Par value	$ 42,174	$ 50,237

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.

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+ Details

Federal Home Loan Bank of Chicago 10-K