Number of segment subsidiaries

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- Definition

Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.

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Current period adjustment resulting from gains and losses on intercompany foreign currency transactions that are of a long-term-investment nature because settlement is not planned or anticipated in the foreseeable future. Resulting from the entities to the transaction being consolidated, combined, or accounted for by the equity method in the reporting entity's financial statements.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 20

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Paragraph 31

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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-Name Regulation S-X (SX)

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-Section 03

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-Name Regulation S-X (SX)

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-Section 02

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

+ References

No definition available.

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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-Publisher FASB

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-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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Disclosure About Segments of Enterprise and Related Information (Details) (USD $)	3 Months Ended								9 Months Ended	12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Sep. 30, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Segment information [Line Items]
Number of operating segments					4				6	4
Revenue by segment [Abstract]
Revenue	$ 128,530,000	$ 147,974,000	$ 145,376,000	$ 150,102,000	$ 100,719,000	$ 91,766,000	$ 100,415,000	$ 110,038,000		$ 571,982,000	$ 402,938,000	$ 400,575,000
Depreciation and Amortization [Abstract]
Depreciation and Amortization										38,750,000	36,148,000	35,146,000
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										128,461,000	29,156,000	7,730,000
Other expense										(505,000)	(785,000)	(7,313,000)
Income before provision (benefit) for income taxes										127,956,000	28,371,000	417,000
Capital Expenditures										31,262,000	44,220,000	14,534,000
Assets	948,131,000				865,313,000					948,131,000	865,313,000	849,704,000
Revenue by product line [Abstract]
Revenue	128,530,000	147,974,000	145,376,000	150,102,000	100,719,000	91,766,000	100,415,000	110,038,000		571,982,000	402,938,000	400,575,000
Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										100.00%	100.00%	100.00%
United States [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										55.00%	49.00%	66.00%
Foreign net sales [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										45.00%	51.00%	34.00%
Advanced Ceramic Operations [Member]
Segment information [Line Items]
Reallocation of inter-company corporate charges										(8,500,000)
Revenue by segment [Abstract]
Revenue										277,541,000	152,578,000	221,751,000
Depreciation and Amortization [Abstract]
Depreciation and Amortization										9,790,000	9,238,000	10,389,000
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										60,253,000	(23,113,000)	25,031,000
Capital Expenditures										6,276,000	6,811,000	4,880,000
Assets	474,633,000				414,425,000					474,633,000	414,425,000	406,866,000
Revenue by product line [Abstract]
Revenue										277,541,000	152,578,000	221,751,000
Advanced Ceramic Operations [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										49.00%	38.00%	55.00%
Advanced Ceramic Operations [Member] \| United States [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										43.00%	34.00%	53.00%
Advanced Ceramic Operations [Member] \| Foreign net sales [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										6.00%	4.00%	2.00%
Advanced Ceramic Operations [Member] \| Defense [Member]
Revenue by segment [Abstract]
Revenue										203,058,000	105,362,000	189,028,000
Revenue by product line [Abstract]
Revenue										203,058,000	105,362,000	189,028,000
Advanced Ceramic Operations [Member] \| Industrial [Member]
Revenue by segment [Abstract]
Revenue										35,067,000	26,684,000	16,177,000
Revenue by product line [Abstract]
Revenue										35,067,000	26,684,000	16,177,000
Advanced Ceramic Operations [Member] \| Energy [Member]
Revenue by segment [Abstract]
Revenue										17,858,000	2,117,000	2,053,000
Revenue by product line [Abstract]
Revenue										17,858,000	2,117,000	2,053,000
Advanced Ceramic Operations [Member] \| Automotive [Member]
Revenue by segment [Abstract]
Revenue										10,364,000	10,057,000	5,006,000
Revenue by product line [Abstract]
Revenue										10,364,000	10,057,000	5,006,000
Advanced Ceramic Operations [Member] \| Commercial (Orthodontics) [Member]
Revenue by segment [Abstract]
Revenue										11,194,000	8,358,000	9,487,000
Revenue by product line [Abstract]
Revenue										11,194,000	8,358,000	9,487,000
ESK Ceramics [Member]
Segment information [Line Items]
Reallocation of inter-company corporate charges										1,800,000
Revenue by segment [Abstract]
Revenue										163,592,000	130,747,000	105,117,000
Depreciation and Amortization [Abstract]
Depreciation and Amortization										12,742,000	12,625,000	11,686,000
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										30,865,000	21,133,000	(21,501,000)
Capital Expenditures										5,278,000	2,497,000	426,000
Assets	170,193,000				173,387,000					170,193,000	173,387,000	207,733,000
Revenue by product line [Abstract]
Revenue										163,592,000	130,747,000	105,117,000
ESK Ceramics [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										25.00%	31.00%	23.00%
ESK Ceramics [Member] \| United States [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										3.00%	5.00%	3.00%
ESK Ceramics [Member] \| Foreign net sales [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										22.00%	26.00%	20.00%
Thermo Materials [Member]
Segment information [Line Items]
Reallocation of inter-company corporate charges										4,200,000
Revenue by segment [Abstract]
Revenue										98,895,000	98,770,000	66,116,000
Depreciation and Amortization [Abstract]
Depreciation and Amortization										8,015,000	6,176,000	4,878,000
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										20,029,000	33,951,000	14,712,000
Capital Expenditures										13,780,000	32,087,000	7,952,000
Assets	172,806,000				149,960,000					172,806,000	149,960,000	105,332,000
Revenue by product line [Abstract]
Revenue										98,895,000	98,770,000	66,116,000
Thermo Materials [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										17.00%	24.00%	15.00%
Thermo Materials [Member] \| United States [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										4.00%	5.00%	6.00%
Thermo Materials [Member] \| Foreign net sales [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										13.00%	19.00%	9.00%
Boron [Member]
Segment information [Line Items]
Reallocation of inter-company corporate charges										2,500,000
Number of segment subsidiaries	3									3
Land owned related to the production of boron (in acres)	155									155
Revenue by segment [Abstract]
Revenue										55,430,000	35,010,000	28,951,000
Depreciation and Amortization [Abstract]
Depreciation and Amortization										8,203,000	8,109,000	8,193,000
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										16,822,000	(2,385,000)	(11,048,000)
Capital Expenditures										5,928,000	2,825,000	1,276,000
Assets	130,499,000				127,541,000					130,499,000	127,541,000	129,773,000
Revenue by product line [Abstract]
Revenue										55,430,000	35,010,000	28,951,000
Boron [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										9.00%	7.00%	7.00%
Boron [Member] \| United States [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										5.00%	5.00%	4.00%
Boron [Member] \| Foreign net sales [Member] \| Sales Revenue, Goods, Net [Member]
Revenue by geographic concentration [Line Items]
Percentage of net sales from external customers										4.00%	2.00%	3.00%
Intersegment Elimination [Member]
Revenue by segment [Abstract]
Revenue										(23,476,000)	(14,167,000)	(21,360,000)
Segment Income (Loss) from Operations and Income before Provision for Income Taxes [Abstract]
Segment Income (loss) from operations										492,000	(430,000)	536,000
Revenue by product line [Abstract]
Revenue										$ (23,476,000)	$ (14,167,000)	$ (21,360,000)
US Government and government agnecies [Member]
Segment information [Line Items]
Percentage of sales by one customer that accounted for more than 10% of revenue										37.60%	17.50%	40.80%