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
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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

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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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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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
-Subparagraph (SX 210.5-02.19(b),22(b))
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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 (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 06, 2019	Oct. 29, 2018	Aug. 08, 2018	May 03, 2018	Feb. 02, 2018	Oct. 31, 2017	Aug. 02, 2017	May 04, 2017	Feb. 09, 2017	Dec. 31, 2018
Subsequent Event [Line Items]
Line of Credit Facility, Current Borrowing Capacity										$ 100.0
Dividends declared date		Oct. 29, 2018	Aug. 08, 2018	May 03, 2018	Feb. 02, 2018	Oct. 31, 2017	Aug. 02, 2017	May 04, 2017	Feb. 09, 2017
Dividend amount to be paid, per common share (in dollars per share)		$ 0.4350	$ 0.4250	$ 0.4150	$ 0.4050	$ 0.3950	$ 0.3850	$ 0.3750	$ 0.3650
Date dividend is payable		Dec. 05, 2018	Sep. 04, 2018	Jun. 01, 2018	Mar. 09, 2018	Dec. 05, 2017	Sep. 01, 2017	Jun. 02, 2017	Mar. 09, 2017
Date shareholders must be on record for dividend		Nov. 19, 2018	Aug. 20, 2018	May 18, 2018	Feb. 22, 2018	Nov. 17, 2017	Aug. 14, 2017	May 19, 2017	Feb. 22, 2017
Subsequent Event
Subsequent Event [Line Items]
Dividends declared date	Feb. 06, 2019
Dividend amount to be paid, per common share (in dollars per share)	$ 0.4450
Date dividend is payable	Mar. 12, 2019
Date shareholders must be on record for dividend	Feb. 25, 2019