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Dividends Declared Per Share (Detail)	3 Months Ended
	Mar. 31, 2019 $ / shares
Group One
Dividends Payable [Line Items]
Declaration Date	Apr. 24, 2019
Date Paid (Payable)	May 29, 2019
Shareholder of Record Date	May 15, 2019
Dividend Amount	$ 0.370
Group Two
Dividends Payable [Line Items]
Declaration Date	Jan. 30, 2019
Date Paid (Payable)	Feb. 28, 2019
Shareholder of Record Date	Feb. 14, 2019
Dividend Amount	$ 0.370
Group Three
Dividends Payable [Line Items]
Declaration Date	Oct. 24, 2018
Date Paid (Payable)	Nov. 29, 2018
Shareholder of Record Date	Nov. 15, 2018
Dividend Amount	$ 0.365
Group Four
Dividends Payable [Line Items]
Declaration Date	Jul. 25, 2018
Date Paid (Payable)	Aug. 29, 2018
Shareholder of Record Date	Aug. 15, 2018
Dividend Amount	$ 0.365
Group Five
Dividends Payable [Line Items]
Declaration Date	Apr. 25, 2018
Date Paid (Payable)	May 29, 2018
Shareholder of Record Date	May 15, 2018
Dividend Amount	$ 0.365
Group Six
Dividends Payable [Line Items]
Declaration Date	Jan. 30, 2018
Date Paid (Payable)	Feb. 28, 2018
Shareholder of Record Date	Feb. 14, 2018
Dividend Amount	$ 0.365

X

- Definition

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

+ References

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

- Definition

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

+ References

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

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

+ References

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

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

+ References

No definition available.

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- Definition

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+ References

No definition available.

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