Stock Repurchase Programs [Line Items]

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29,30)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Details

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Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 31, 2015
Stock Repurchase Programs [Line Items]
Stock repurchase program, authorized amount		$ 500,000,000
Cumulative repurchases, shares		22.5
Cumulative repurchases, value		$ 446,000,000
Common stock average price		$ 19.87
Repurchase of stock, value		$ 146,331,000	$ 299,949,000
January Twenty Fifteen Share Repurchase Program
Stock Repurchase Programs [Line Items]
Stock repurchase program termination date		Dec. 31, 2016
Maximum
Stock Repurchase Programs [Line Items]
Stock repurchase program, authorized amount				$ 500,000,000
Scenario, Forecast \| Minimum
Stock Repurchase Programs [Line Items]
Repurchase of stock, value	$ 200,000,000