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Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Accounts receivable and accrued revenue, ALLOWANCE | $ 27 | $ 29
Notes receivable, ALLOWANCE | 29 | 32
Accounts and notes receivable, ALLOWANCE | $ 89 | $ 91
Common stock authorized (in shares) | 350,000,000.0 | 350,000,000.0
Common stock outstanding (in shares) | 289,500,000 | 288,900,000
Consumers Energy Company |  |
Accounts receivable and accrued revenue, ALLOWANCE | $ 27 | $ 29
Common stock authorized (in shares) | 125,000,000.0 | 125,000,000.0
Common stock outstanding (in shares) | 84,100,000 | 84,100,000

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