Share Repurchase Program (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Aug. 03, 2007
Share Repurchase Program
Share Repurchase Program	$ 150,000			$ 150,000			$ 30,000
Number of common shares purchased during period under the program	249,754			551,598
Acquisition of treasury stock	$ 17,854	$ 11,753	$ 10,392	$ 39,999	$ 0
Treasury stock shares	2,831,168			2,831,168		2,279,570
Treasury stock, at cost	$ 123,834			$ 123,834		$ 83,835

No definition available.

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- Definition

Represents the number of common shares that were repurchased during the period. Recorded using the cost method.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of previously issued common shares repurchased by the issuing entity and held in treasury.

+ References

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- Definition

Amount allocated to previously issued common shares repurchased by the issuing entity and held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

+ References

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