Aggregate liquidation preferences.

No definition available.

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- Definition

Preferred stock issuance cost.

+ References

No definition available.

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- Definition

Stock repurchased and retired during period average price per share.

+ References

No definition available.

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- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References

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-Name Accounting Standards Codification
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- Definition

Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

+ References

No definition available.

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- Definition

The redemption (or callable) amount of currently redeemable preferred stock. Includes amounts representing dividends not currently declared or paid but which will be payable under the redemption features or for which ultimate payment is solely within the control of the issuer.

+ References

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

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- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased and retired during the period.

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Capital Structure - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	12 Months Ended
	Jan. 03, 2017	Sep. 20, 2016	Jul. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 03, 2017	Feb. 08, 2017
Class of Stock [Line Items]
Additional paid in capital				$ 967.5	$ 954.7
Aggregate liquidation preferences				525.0	525.0
Preferred stock issuance cost				13.1	13.1
Stock repurchase program, remaining authorized repurchase amount				$ 220.0	$ 220.0
Preferred Stock, Redemption Amount	$ 133.2						$ 160.0
Redemption price per share				$ 25	$ 25
Preference shares liquidation preference, value				$ 250.0
5.625% Preference Shares
Class of Stock [Line Items]
Preferred stock issuance cost				$ 8.7
Preference shares, issued				10,000,000	10,000,000
Preference shares, rate		5.625%		5.625%	5.625%
Redemption price per share				$ 25	$ 25
7.401% Preference Shares
Class of Stock [Line Items]
Preference shares, rate	7.401%				7.401%
Redemption price per share							$ 25
7.250% Preference Shares
Class of Stock [Line Items]
Preference shares, rate			7.25%		7.25%
Open Markets
Class of Stock [Line Items]
Stock repurchased during period, shares					648,941
Stock repurchased during period, value					$ 30.0
Stock repurchased during period, average price per share					$ 46.23
Repurchase Program 2017
Class of Stock [Line Items]
Stock repurchase program, authorized amount								$ 250.0
Additional paid-in capital \| Preference Shares
Class of Stock [Line Items]
Preference shares redeemed and cancelled				$ 0.0	$ (293.2)	$ 0.0