Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
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

Face amount per share of no-par value common stock.

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