Share Repurchase Program (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2020
Aggregate cost, including fees	$ 117.1
2017 Share Repurchase Program
Stock repurchase program, remaining authorized repurchase amount		$ 338.4

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

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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