Increase in amount authorized under the Company's board-approved share repurchase program.

No definition available.

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- Definition

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.

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No definition available.

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Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

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

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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.

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Share Repurchase Program (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		1 Months Ended	3 Months Ended		100 Months Ended
	Nov. 13, 2018	May 06, 2019	Mar. 31, 2019	Mar. 31, 2018	May 06, 2019
Share Repurchase Program
Increase in authorized amount	$ 1,000,000
Cumulative authorized amount	$ 11,800,000
Authorization effective period	3 years
Remaining balance under share repurchase program			$ 679,600
Common stock repurchased, shares			927	2,188
Common stock repurchased, average price per share			$ 347.09	$ 251.08
Common stock repurchased, value			$ 321,846	$ 549,428
Subsequent event [Member]
Share Repurchase Program
Common stock repurchased, shares		100			73,400
Common stock repurchased, average price per share		$ 377.59			$ 151.58
Common stock repurchased, value		$ 52,100			$ 11,100,000