Income Taxes (Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Reconciliation of the Beginning and Ending Amount of Unrecognized Tax Benefits [Roll Forward]
Beginning balance	$ 77,849	$ 69,801
Additions based on tax positions related to the current year	10,168	9,293
Additions for tax positions of prior years	10,325	7,656
Reductions related to audit settlements		(137)
Reductions related to the expiration of statutes of limitations	(8,436)	(8,764)
Ending balance	$ 89,906	$ 77,849

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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