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Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Equity [Abstract]
Common shares, shares authorized (in shares)	100,000,000						100,000,000		100,000,000
Preferred stock, shares authorized (in shares)	50,000,000						50,000,000		50,000,000
Cash dividends declared per common share (in usd per share)	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.31	$ 0.15	$ 0.41
Dividend declared							$ 8.1	$ 22.1
Total authorizations which remain available for use	$ 110.0						$ 110.0
Common shares acquired (in shares)							0	0
Deferred tax (benefit) expense included in OCI	$ (3.2)			$ 1.9			$ (8.3)	$ 7.7

X

- Definition

The remaining amount authorized by an entity's Board of Directors for stock repurchase or debt repayment.

+ References

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Aggregate dividends declared during the period for each share of common stock outstanding.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Number of shares that have been repurchased during the period and are being held in treasury.

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