Receivables (Receivables Sold Under The Agreement) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Accounts Receivable [Line Items]
Fair value of deferred proceeds	$ 214	$ 188
IPL [Member]
Accounts Receivable [Line Items]
Fair value of deferred proceeds	214	188
Financing Receivable [Member] | IPL [Member]
Accounts Receivable [Line Items]
Customer accounts receivable	125	114
Unbilled utility revenues	104	92
Receivables sold to third party	229	206
Less: cash proceeds	1	1
Deferred proceeds	228	205
Less: allowance for expected credit losses	14	17
Fair value of deferred proceeds	214	188
Financing Receivable [Member] | IPL [Member] | Financial Asset, Past Due
Accounts Receivable [Line Items]
Outstanding receivables past due	$ 22	$ 27