Aggregate dividends declared during the period for each share of common stock outstanding.

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)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Gross number of share options (or share units) granted during the period.

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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.

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Subsequent Events (Details) - $ / shares			3 Months Ended
Subsequent Events (Details) - $ / shares	Apr. 24, 2018	Apr. 11, 2018	Mar. 31, 2018	Mar. 31, 2017	Apr. 30, 2018	Mar. 23, 2017
Subsequent Event [Line Items]
Dividends declared per share (in US dollars per share)			$ 0.47	$ 0.47
Subsequent Event
Subsequent Event [Line Items]
Dividends declared per share (in US dollars per share)		$ 0.47
Stock options granted (in shares)	562,000
Restricted Stock
Subsequent Event [Line Items]
Granted shares (in shares)			0
Restricted Stock \| Subsequent Event
Subsequent Event [Line Items]
Granted shares (in shares)	914,000
Performance Based Restricted Stock \| Subsequent Event
Subsequent Event [Line Items]
Granted shares (in shares)	352,500
Vesting period	3 years
Amended Credit Agreement \| Term Loan \| Line of Credit \| London Interbank Offered Rate (LIBOR)
Subsequent Event [Line Items]
Basis spread on variable rate						2.25%
Amended Credit Agreement \| Term Loan \| Line of Credit \| London Interbank Offered Rate (LIBOR) \| Subsequent Event
Subsequent Event [Line Items]
Basis spread on variable rate					2.00%