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

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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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.

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No definition available.

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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.

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

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Equity and Dividends (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	2 Months Ended	12 Months Ended
	Feb. 26, 2018	Dec. 31, 2017	Dec. 31, 2016
Dividends Payable [Line Items]
Preferred shares issued		0
Stock repurchased during period, shares		0	1,460,000
Stock repurchased during period, per share			$ 25.16
Subsequent Event [Member]
Dividends Payable [Line Items]
Dividends declared (usd per share)	$ 0.17
Dividends, common stock	$ 18,246
Payment date	Mar. 09, 2018
Record date	Feb. 16, 2018