Share Based Award Options exercised data (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement [Abstract]
Intrinsic value of options exercised	$ 32,915	$ 22,976	$ 51,105
Cash received from exercise of stock options	13,193	7,732	14,275
Tax benefit from stock option exercises	$ 5,179	$ 9,653	$ 12,617

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Amount of tax benefit from exercise of option under share-based payment arrangement.

+ References

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=SL79508275-113901

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-Publisher FASB
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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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