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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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- Definition

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

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- Definition

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

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Schedule of Dividends Authorized and Declared Cash Dividends to Common Stockholders (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2018	Jul. 18, 2018	Apr. 19, 2018	Jan. 31, 2018
Installment First Quarter Of Fiscal Year
Dividends Payable [Line Items]
Declaration Date	Jan. 31, 2018
Payment Date	Mar. 14, 2018
Record Date (close of business)	Feb. 28, 2018
Dividend Amount Per Share of Common Stock				$ 0.250
Installment Second Quarter Of Fiscal Year
Dividends Payable [Line Items]
Declaration Date	Apr. 19, 2018
Payment Date	May 30, 2018
Record Date (close of business)	May 16, 2018
Dividend Amount Per Share of Common Stock			$ 0.250
Installment Third Quarter Of Fiscal Year
Dividends Payable [Line Items]
Declaration Date	Jul. 18, 2018
Payment Date	Aug. 29, 2018
Record Date (close of business)	Aug. 15, 2018
Dividend Amount Per Share of Common Stock		$ 0.250