Stockholders' Equity (Summary of Dividends Declared) (Details) - $ / shares			9 Months Ended
May 02, 2019	Feb. 06, 2019	Sep. 30, 2019
Equity [Abstract]
Declaration Date	May 02, 2019	Feb. 06, 2019
Dividend per common share (in usd per share)	$ 0.4550	$ 0.4450	$ 0.9000
Record Date	May 20, 2019	Feb. 25, 2019
Payment Date	Jun. 04, 2019	Mar. 12, 2019

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=120397183&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=121583591&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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