Stock Repurchase Program - Summary of Stock Repurchase Activity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity [Abstract]
Total number of shares repurchased		536,743			393,975	958,459
Average price paid per share (in dollars per share)		$ 34.83			$ 38.78	$ 33.73
Total value of shares repurchased	$ 15.3	$ 18.7	$ 11.3	$ 2.3	$ 15.3	$ 32.3

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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