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

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

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

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

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 - Additional Information (Details) $ / shares in Units, £ in Millions, $ in Millions			3 Months Ended	9 Months Ended
	Nov. 07, 2018 USD ($) $ / shares	Aug. 09, 2018 $ / shares	Sep. 30, 2017 $ / shares	Sep. 30, 2018 $ / shares	Sep. 30, 2017 $ / shares	Nov. 07, 2018 GBP (£)
Subsequent Event [Line Items]
Dividends payable, date declared				Aug. 09, 2018
Common stock dividends per share declared		$ 0.07	$ 0.06	$ 0.21	$ 0.165
Dividend payable, date paid				Sep. 21, 2018
Subsequent Event
Subsequent Event [Line Items]
Dividends payable, date declared	Nov. 07, 2018
Common stock dividends per share declared	$ 0.07
Dividend payable, date paid	Dec. 21, 2018
Dividends payable record date	Nov. 30, 2018
Subsequent Event \| Tranche One Extending \| Club Facility
Subsequent Event [Line Items]
Line of credit, commitment \| $	$ 165.0
Subsequent Event \| Tranche Two Extending \| Club Facility
Subsequent Event [Line Items]
Line of credit, commitment \| £						£ 60.0