CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Millions	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Non-controlling Interests [Member]	Total
Balance at Dec. 31, 2011	$ 4.7	$ 333.4	$ 963.2	$ (45.5)	$ (514.2)	$ 26.4	$ 768.0
Net income	0	0	74.1	0	0	2.1	76.2us-gaap_ProfitLoss
Other comprehensive income (loss)	0	0	0	(5.8)	0	(0.6)	(6.4)
Dividends declared	0	0	(4.4)	0	0	0	(4.4)us-gaap_Dividends
Dividends to non-controlling interest	0	0	0	0	0	(5.4)	(5.4)
Capital contributions by non-controlling interests	0	0	0	0	0	0.8	0.8
Purchase of common stock for treasury	0	0	0	0	(27.7)	0	(27.7)
Issuance of shares pursuant to employee stock compensation plans	0	8.1	0	0	0	0	8.1
Income tax benefit arising from employee stock compensation plans	0	0.8	0	0	0	0	0.8
Stock based compensation	0	3.6	0	0	0	0	3.6
Balance at Dec. 31, 2012	4.7	345.9	1,032.9	(51.3)	(541.9)	23.3	813.6
Net income	0	0	80.3	0	0	3.1	83.4us-gaap_ProfitLoss
Other comprehensive income (loss)	0	0	0	20.0	0	(1.7)	18.3
Dividends declared	0	0	(6.9)	0	0	0	(6.9)us-gaap_Dividends
Dividends to non-controlling interest	0	0	0	0	0	(2.4)	(2.4)
Purchase of common stock for treasury	0	0	0	0	(51.8)	0	(51.8)
Equity reclassification adjustment to non-controlling interests	0	(4.6)				4.6	0
Issuance of shares pursuant to employee stock compensation plans	0	12.2	0	0	0	0	12.2
Income tax benefit arising from employee stock compensation plans	0	2.8	0	0	0	0	2.8
Stock based compensation	0	5.2	0	0	0	0	5.2
Balance at Dec. 31, 2013	4.7	361.5	1,106.3	(31.3)	(593.7)	26.9	874.4
Net income	0	0	92.4	0	0	3.1	95.5us-gaap_ProfitLoss
Other comprehensive income (loss)	0	0	0	(81.6)	0	(1.0)	(82.6)
Dividends declared	0	0	(6.9)	0	0	0	(6.9)us-gaap_Dividends
Dividends to non-controlling interest	0	0	0	0	0	(3.3)	(3.3)
Purchase of non-controlling interest shares	0	(2.1)	0	0	0	0	(2.1)
Acquisition of AMCOL	0	0	0	0	0	0.2	0.2
Issuance of shares pursuant to employee stock compensation plans	0.1	3.3	0	0	0	0	3.4
Income tax benefit arising from employee stock compensation plans	0	4.4	0	0	0	0	4.4
Stock based compensation	0	5.9	0	0	0	0	5.9
Balance at Dec. 31, 2014	$ 4.8	$ 373.0	$ 1,191.8	$ (112.9)	$ (593.7)	$ 25.9	$ 888.9

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Amount of increase in non controlling interest from sale of a portion of the parent's controlling interest.

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Gross value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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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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