Subsequent Events (Details) - $ / shares	Feb. 13, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Shares remaining under existing repurchase program		2,300,000
Subsequent Event
Subsequent Event [Line Items]
Additional number of shares authorized to be repurchased	10,000,000
Quarterly dividend per share	$ 0.28
Declaration date	Feb. 13, 2018
Record date	Feb. 23, 2018
Payment date	Mar. 15, 2018

Stock Repurchase Program, Additional Number of Shares Authorized to be Repurchased

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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