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

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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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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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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No definition available.

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Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Millions, ¥ in Billions						3 Months Ended		6 Months Ended
	Aug. 08, 2018 $ / shares	Jul. 31, 2018 USD ($)	Jul. 31, 2018 JPY (¥)	May 02, 2018 $ / shares	Feb. 14, 2018 $ / shares	Jun. 30, 2018 $ / shares	Jun. 30, 2017 $ / shares	Jun. 30, 2018 $ / shares	Jun. 30, 2017 $ / shares	Jul. 31, 2018 JPY (¥)
Subsequent Event [Line Items]
Cash dividends declared (in dollars per share)				$ 2.28	$ 2.28	$ 2.28	$ 2.00	$ 4.56	$ 4.00
Subsequent event [Member]
Subsequent Event [Line Items]
Cash dividends declared (in dollars per share)	$ 2.28
Subsequent event [Member] \| Unsecured Debt [Member] \| Line of Credit [Member]
Subsequent Event [Line Items]
Borrowing capacity		$ 424.9								¥ 47.5
Repayments of Debt		$ 391.3	¥ 43.8