Stock-Based Compensation (Details 1) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assumptions used in valuing the options granted
Weighted-average grant-date fair value per option (in usd per share)	$ 23.41	$ 14.46
Stock-Based Compensation
Stock option expense	$ 21us-gaap_StockOptionPlanExpense	$ 13us-gaap_StockOptionPlanExpense	$ 10us-gaap_StockOptionPlanExpense
Restricted stock and unit awards expense	79us-gaap_RestrictedStockExpense	83us-gaap_RestrictedStockExpense	80us-gaap_RestrictedStockExpense
Total stock-based compensation expense	100	96	90
Tax benefit	38	37	35
Minimum Range [Member]
Assumptions used in valuing the options granted
Risk-free average interest rate	0.10%	0.10%
Dividend yield	1.80%	2.09%
Volatility	18.00%	29.00%
Expected life	6 years 3 months	6 years 1 month 6 days
Maximum Range [Member]
Assumptions used in valuing the options granted
Risk-free average interest rate	2.90%	2.90%
Dividend yield	1.40%	2.07%
Volatility	41.00%	45.00%
Expected life	6 years 2 months 16 days	6 years 2 months 12 days
Group of Individuals Transferred to MHE [Member]
Stock-Based Compensation
Total stock-based compensation expense			$ 5

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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