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Retirement Plans and Employee Stock Purchase Plans (Tables)
12 Months Ended
Dec. 31, 2019
Retirement Plans and Employee Stock Purchase Plans  
Schedule of purchases made under the 2009 Employee Stock Purchase Plans

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Year ended December 31,

 

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2019

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2018

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2017

 

Number of shares purchased

    

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65,148

    

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60,950

    

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88,362

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Average price of shares purchased

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$

48.58

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$

49.85

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$

33.96

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