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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Balance Type:	na
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- Definition

Start date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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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

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			3 Months Ended		9 Months Ended
	Nov. 07, 2017	Oct. 26, 2017	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Subsequent Event [Line Items]
Dividends declared per share			$ 0.06	$ 0.06	$ 0.18	$ 0.18
Subsequent Event [Member]
Subsequent Event [Line Items]
Redemption period, start date		Nov. 27, 2017
Dividends declared per share	$ 0.06
Dividend declared date	Nov. 07, 2017
Dividend declared payable date	Dec. 08, 2017
Dividend payable, record date	Nov. 28, 2017
Subsequent Event [Member] \| 2022 Notes [Member]
Subsequent Event [Line Items]
Redemption price, percentage of principal amount redeemed		104.031%
Subsequent Event [Member] \| DSS Notes [Member]
Subsequent Event [Line Items]
Redemption price, percentage of principal amount redeemed		105.00%