Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data	Sep. 30, 2011	Dec. 31, 2010
MEHC shareholders' equity:
Common stock, par value	$ 0.00	$ 0.00
Common stock, shares authorized	115	115
Common stock, shares issued	75	75
Common stock, shares outstanding	75	75

Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.

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