Stock Repurchase Programs [Line Items]

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- Definition

Stock Repurchased During Period, Average Price Per Share

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- Definition

Amount of stock repurchase plan authorized.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

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- Definition

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 31, 2018	Jan. 31, 2015
Stock Repurchase Programs [Line Items]
Stock repurchase program, authorized amount				$ 500,000,000
Stock Repurchased During Period, Shares				6.8
Cumulative repurchases, value		$ 832,356,000	$ 200,304,000	$ 146,331,000
Treasury stock average price per share				$ 21.39
Cumulative repurchases, shares		21.6	5.8	22.5
Cumulative repurchases, value		$ 823,500,000	$ 200,000,000	$ 446,000,000
Common stock average price		$ 38.06	$ 34.30	$ 19.87
Scenario, Forecast
Stock Repurchase Programs [Line Items]
Cumulative repurchases, value	$ 500,000,000
Maximum
Stock Repurchase Programs [Line Items]
Stock repurchase program, authorized amount					$ 1,500,000,000	$ 500,000,000