Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 45
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-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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Earnings Per Share (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		79 Months Ended
	Aug. 07, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Aug. 07, 2017
Earnings Per Share
Common stock repurchased, shares		3,475	2,075	5,304	3,306
Common stock repurchased, average price per share		$ 245.26	$ 262.17	$ 253.13	$ 259.14
Common stock repurchased, value		$ 852,226	$ 544,165	$ 1,342,538	$ 856,802
Subsequent event [Member]
Earnings Per Share
Common stock repurchased, shares	200					62,400
Common stock repurchased, average price per share	$ 207.21					$ 132.00
Common stock repurchased, value	$ 35,000					$ 8,200,000