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Amount of stock repurchase plan authorized.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions						12 Months Ended
	Mar. 01, 2021	Nov. 05, 2020	Aug. 06, 2020	May 07, 2020	Feb. 24, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 21, 2018
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)						150,000,000	150,000,000		100,000,000
Dividends paid						$ 22.0	$ 20.8	$ 18.9
Dividends paid (in dollars per share)						$ 0.49	$ 0.45	$ 0.41
Dividends declared per share (in dollars per share)		$ 0.13	$ 0.12	$ 0.12	$ 0.12	$ 0.49	$ 0.45	$ 0.41
Number of shares repurchased (in shares)						407,971	767,681	588,489
Average price per share (in dollars per share)						$ 25.62	$ 28.66	$ 26.20
Total repurchase costs						$ 10.4	$ 22.0	$ 15.5
Subsequent Event
Subsequent Event [Line Items]
Dividends declared per share (in dollars per share)	$ 0.13
2020 Program
Subsequent Event [Line Items]
Authorized increase to stock repurchase plan					$ 60.0
Common stock available for future share repurchases, amount						$ 49.6
2017 Program
Subsequent Event [Line Items]
Common stock available for future share repurchases, amount					$ 0.4