CMC Materials (CCMP) 10-Q 8 Aug 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	9 Months Ended
	Jun. 30, 2014	Jul. 31, 2014	Mar. 31, 2014
Document and Entity Information [Abstract]	'	'	'
Entity Registrant Name	'CABOT MICROELECTRONICS CORP	'	'
Entity Central Index Key	'0001102934	'	'
Current Fiscal Year End Date	'--09-30	'	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Public Float	'	'	$1,030,587,000
Entity Common Stock, Shares Outstanding	'	23,778,720	'
Document Fiscal Year Focus	'2014	'	'
Document Fiscal Period Focus	'Q3	'	'
Document Type	'10-Q	'	'
Amendment Flag	'false	'	'
Document Period End Date	30-Jun-14	'	'

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
CONSOLIDATED STATEMENTS OF INCOME [Abstract]	'	'	'	'
Revenue	$108,358	$109,968	$308,329	$316,865
Cost of goods sold	56,632	55,359	162,364	163,872
Gross profit	51,726	54,609	145,965	152,993
Operating expenses:	'	'	'	'
Research, development and technical	15,368	15,149	44,303	45,538
Selling and marketing	6,489	6,470	19,667	20,625
General and administrative	11,380	10,776	33,182	34,017
Total operating expenses	33,237	32,395	97,152	100,180
Operating income	18,489	22,214	48,813	52,813
Interest expense	832	907	2,547	2,732
Other income (expense), net	-132	248	588	1,565
Income before income taxes	17,525	21,555	46,854	51,646
Provision for income taxes	4,223	5,261	12,149	14,543
Net income	$13,302	$16,294	$34,705	$37,103
Basic earnings per share (in dollars per share)	$0.55	$0.70	$1.45	$1.60
Weighted average basic shares outstanding	23,752,770	22,951,408	23,768,858	22,897,320
Diluted earnings per share (in dollars per share)	$0.53	$0.68	$1.39	$1.55
Weighted average diluted shares outstanding (in shares)	24,613,492	23,739,359	24,704,369	23,697,229

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]	'	'	'	'
Net income	$13,302	$16,294	$34,705	$37,103
Other comprehensive income:	'	'	'	'
Foreign currency translation adjustment	3,644	-4,077	-1,568	-15,828
Unrealized Gain on Investment	0	0	151	0
Other comprehensive income (loss), net of tax	3,644	-4,077	-1,417	-15,828
Total comprehensive income	$16,946	$12,217	$33,288	$21,275

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$265,515	$226,029
Accounts receivable, less allowance for doubtful accounts of $1,422 at June 30, 2014, and $1,532 at September 30, 2013	55,375	54,640
Inventories	70,904	63,786
Prepaid expenses and other current assets	12,917	10,684
Deferred income taxes	8,120	7,659
Total current assets	412,831	362,798
Property, plant and equipment, net	105,944	111,985
Goodwill	43,882	44,306
Other intangible assets, net	7,849	9,785
Deferred income taxes	8,784	10,291
Other long-term assets	10,688	12,427
Total assets	589,978	551,592
Current liabilities:	'	'
Accounts payable	12,428	16,663
Current portion of long-term debt	8,750	10,938
Accrued expenses, income taxes payable and other current liabilities	27,465	40,620
Total current liabilities	48,643	68,221
Long-term debt, net of current portion	166,250	150,937
Deferred income taxes	1,018	1,559
Other long-term liabilities	9,525	7,433
Total liabilities	225,436	228,150
Commitments and contingencies (Note 9)	'	'
Stockholders' equity:	'	'
Common Stock: Authorized: 200,000,000 shares, $0.001 par value; Issued: 31,889,633 shares at June 30, 2014, and 30,213,577 shares at September 30, 2013	32	30
Capital in excess of par value of common stock	432,671	376,206
Retained earnings	211,896	177,191
Accumulated other comprehensive income	16,019	17,436
Treasury stock at cost, 7,997,555 shares at June 30, 2014, and 6,866,675 shares at September 30, 2013	-296,076	-247,421
Total stockholders' equity	364,542	323,442
Total liabilities and stockholders' equity	$589,978	$551,592

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, except Share data, unless otherwise specified
Current assets	'	'
Allowance for doubtful accounts	$1,422	$1,532
Stockholders' equity	'	'
Common stock: Authorized	200,000,000	200,000,000
Common stock: par value	$0.00	$0.00
Common stock: Issued	31,889,633	30,213,577
Treasury stock at cost, shares	7,997,555	6,866,675

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:	'	'
Net income	$34,705	$37,103
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation and amortization	14,937	15,576
Provision for doubtful accounts	-216	213
Share-based compensation expense	10,897	10,317
Deferred income tax expense (benefit)	641	-774
Non-cash foreign exchange (gain)/loss	-191	4,817
(Gain)/loss on disposal of property, plant and equipment	-43	513
Impairment of property, plant and equipment	2,293	38
Other	-253	-2,023
Changes in operating assets and liabilities:	'	'
Accounts receivable	-889	-7,932
Inventories	-7,492	-2,882
Prepaid expenses and other assets	-1,250	-2,771
Accounts payable	-3,839	-2,799
Accrued expenses, income taxes payable and other liabilities	-12,564	4,055
Net cash provided by operating activities	36,736	53,451
Cash flows from investing activities:	'	'
Additions to property, plant and equipment	-10,242	-10,209
Proceeds from the sale of property, plant and equipment	190	16
Proceeds from the sale of investments	2,305	25
Other investing activities	1,062	0
Net cash used in investing activities	-6,685	-10,168
Cash flows from financing activities:	'	'
Issuance of long-term debt	17,500	0
Repayment of long-term debt	-4,375	-6,563
Repurchases of common stock	-47,709	-31,293
Net proceeds from issuance of stock	41,661	21,065
Tax benefits associated with share-based compensation expense	2,788	733
Debt issuance costs	-550	0
Principal payments under capital lease obligations	0	-21
Net cash provided by (used in) financing activities	9,315	-16,079
Effect of exchange rate changes on cash	120	-4,052
Increase in cash and cash equivalents	39,486	23,152
Cash and cash equivalents at beginning of period	226,029	178,459
Cash and cash equivalents at end of period	265,515	201,611
Supplemental disclosure of non-cash investing and financing activities:	'	'
Purchases of property, plant and equipment in accrued liabilities and accounts payable at the end of the period	945	663
Issuance of restricted stock	$7,785	$5,926

BACKGROUND_AND_BASIS_OF_PRESEN

BACKGROUND AND BASIS OF PRESENTATION	9 Months Ended
	Jun. 30, 2014
BACKGROUND AND BASIS OF PRESENTATION [Abstract]	'
BACKGROUND AND BASIS OF PRESENTATION	'
	CABOT MICROELECTRONICS CORPORATION
	NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
	(Unaudited and in thousands, except share and per share amounts)
	1. BACKGROUND AND BASIS OF PRESENTATION
	Cabot Microelectronics Corporation ("Cabot Microelectronics'', "the Company'', "us'', "we'' or "our'') supplies high-performance polishing slurries and pads used in the manufacture of advanced integrated circuit (IC) devices within the semiconductor industry, in a process called chemical mechanical planarization (CMP). CMP is a polishing process used by IC device manufacturers to planarize or flatten many of the multiple layers of material that are deposited upon silicon wafers in the production of advanced ICs.  Our products play a critical role in the production of advanced IC devices, thereby enabling our customers to produce smaller, faster and more complex IC devices with fewer defects.  We develop, produce and sell CMP slurries for polishing many of the conducting and insulating materials used in IC devices, and also for polishing the disk substrates and magnetic heads used in hard disk drives.  We also develop, manufacture and sell CMP polishing pads, which are used in conjunction with slurries in the CMP process. We also pursue other demanding surface modification applications through our Engineered Surface Finishes (ESF) business where we believe we can leverage our expertise in CMP consumables for the semiconductor industry to develop products for demanding polishing applications in other industries. For additional information, refer to Part 1, Item 1, "Business", in our annual report on Form 10-K for the fiscal year ended September 30, 2013.
	The unaudited consolidated financial statements have been prepared by Cabot Microelectronics Corporation pursuant to the rules of the Securities and Exchange Commission (SEC) and accounting principles generally accepted in the United States of America.  In the opinion of management, these unaudited consolidated financial statements include all normal recurring adjustments necessary for the fair presentation of Cabot Microelectronics' financial position as of June 30, 2014, cash flows for the nine months ended June 30, 2014, and June 30, 2013, and results of operations for the three and nine months ended June 30, 2014, and June 30, 2013.  The results of operations for the three and nine months ended June 30, 2014 may not be indicative of results to be expected for future periods, including the fiscal year ending September 30, 2014.  These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes thereto included in Cabot Microelectronics' annual report on Form 10-K for the fiscal year ended September 30, 2013.
	The consolidated financial statements include the accounts of Cabot Microelectronics and its subsidiaries.  All intercompany transactions and balances between the companies have been eliminated as of June 30, 2014.
	Revision of Prior Period Amounts
	In the third quarter of fiscal 2014, the Company recorded adjustments to prior periods to correct certain items of income tax accounting, which related to fiscal years 2011 through 2013.  The adjustments, totaling $3,635, related to the accounting for intercompany profit in inventory at our foreign branch locations and the accounting for annual incentive costs and related fringe benefits, and are reflected in the Consolidated Balance Sheet table below as of September 30, 2013.  In evaluating the cumulative materiality of the corrections, we considered guidance in Accounting Standard Codification (ASC) Topic 250, "Accounting Changes and Error Corrections", and its subtopics, ASC 250-10-S99-1, "Assessing Materiality" and ASC 250-10-S99-2, "Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements".  We concluded that the cumulative effect of correcting these prior period amounts was not material individually or in the aggregate to any of the prior reporting periods.  We also evaluated the effect that these adjustments would have had on our consolidated financial statements as of and for the three and nine months ended June 30, 2014, and concluded these adjustments would have had a material impact.  As such, we concluded that revision of prior periods for the cumulative effect of these adjustments was appropriate.  Since the cumulative impact of the adjustments is not material to prior periods, we have not amended previously filed reports.  As part of this revision, we also corrected previously disclosed out-of-period adjustments, which were immaterial to their respective prior periods.
	The correction of out-of-period adjustments is reflected in the comparative results for the three and nine months ended June 30, 2013 included in this Form 10-Q.  We intend to present the annual effect of the cumulative corrections to fiscal years 2012 and 2013 in our Annual Report on Form 10-K for the fiscal year ended September 30, 2014 and in any other future filings containing such financial information.
	The following tables summarize the effects of the revisions to the financial statements for the comparative periods of fiscal 2013 (in thousands, except per share data):
	CONSOLIDATED STATEMENTS OF INCOME
		Three Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Income before income taxes	$	21,555		$	-		$	21,555
	Provision for income taxes		6,062			(801	)		5,261
	Net income		15,493			801			16,294
	Basic earnings per share	$	0.68		$	0.02		$	0.7
	Weighted average diluted shares outstanding		23,776			(37	)		23,739
	Diluted earnings per share	$	0.65		$	0.03		$	0.68
		Nine Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Income before income taxes	$	51,646		$	-		$	51,646
	Provision for income taxes		17,030			(2,487	)		14,543
	Net income		34,616			2,487			37,103
	Basic earnings per share	$	1.51		$	0.09		$	1.6
	Weighted average diluted shares outstanding		23,729			(32	)		23,697
	Diluted earnings per share	$	1.46		$	0.09		$	1.55
	CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
		Three Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Net income	$	15,493		$	801		$	16,294
	Other comprehensive income (loss), net of tax		(4,077	)		-			(4,077	)
	Comprehensive income	$	11,416		$	801		$	12,217
		Nine Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Net income	$	34,616		$	2,487		$	37,103
	Other comprehensive income (loss), net of tax		(15,828	)		-			(15,828	)
	Comprehensive income	$	18,788		$	2,487		$	21,275
	CONSOLIDATED BALANCE SHEET
		30-Sep-13
		As			Adjustment			As
		Originally						Revised
		Reported
	Prepaid expenses and other current assets	$	13,598		$	(2,914	)	$	10,684
	Total current assets		365,712			(2,914	)		362,798
	Total assets		554,506			(2,914	)		551,592
	Accrued expenses, income taxes payable and other current liabilities		39,899			721			40,620
	Total current liabilities		67,500			721			68,221
	Total liabilities		227,429			721			228,150
	Retained earnings		180,826			(3,635	)		177,191
	Total stockholders' equity		327,077			(3,635	)		323,442
	Total liabilities and stockholders' equity	$	554,506		$	(2,914	)	$	551,592
	CONSOLIDATED STATEMENT OF CASH FLOWS
		Nine Months Ended June 30, 2013
	As			Adjustment			As
	Originally						Revised
	Reported
Net income	$	34,616		$	2,487		$	37,103
Deferred income tax expense (benefit)		912			(1,686	)		(774	)
Change in accrued expenses, income taxes payable and other current liabilities		4,856			(801	)		4,055
Net cash provided by operating activities	$	53,451		$	-		$	53,451
Results of Operations
The results of operations for the nine months ended June 30, 2014 include an asset impairment charge of $2,111 ($1,475 net of tax) related to certain manufacturing assets recorded in the quarter ended March 31, 2014.  This asset impairment charge included in cost of goods sold reduced our gross profit percentage by 210 basis points during the second quarter of fiscal 2014 and by 70 basis points on a year-to-date basis.  The impairment charge reduced diluted earnings per share by approximately $0.06 on a year-to-date basis.

FAIR_VALUE_OF_FINANCIAL_INSTRU

FAIR VALUE OF FINANCIAL INSTRUMENTS	9 Months Ended
	Jun. 30, 2014
FAIR VALUE OF FINANCIAL INSTRUMENTS [Abstract]	'
FAIR VALUE OF FINANCIAL INSTRUMENTS	'
	2. FAIR VALUE OF FINANCIAL INSTRUMENTS
	Fair value is defined as the price that would be received from the sale of an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date.  The FASB established a three-level hierarchy for disclosure based on the extent and level of judgment used to estimate fair value.  Level 1 inputs consist of valuations based on quoted market prices in active markets for identical assets or liabilities. Level 2 inputs consist of valuations based on quoted prices for similar assets or liabilities, quoted prices for identical assets or liabilities in an inactive market, or other observable inputs. Level 3 inputs consist of valuations based on unobservable inputs that are supported by little or no market activity.
	The following table presents financial instruments, other than long-term debt, that we measured at fair value on a recurring basis at June 30, 2014 and September 30, 2013. See Note 7 for a detailed discussion of our long-term debt. We have chosen to not measure any of our other financial instruments at fair value as we believe their carrying value approximates their fair value. We have classified the following assets in accordance with the fair value hierarchy set forth in the applicable standards. In instances where the inputs used to measure the fair value of an asset fall into more than one level of the hierarchy, we have classified them based on the lowest level input that is significant to the determination of the fair value.
	30-Jun-14	Level 1			Level 2		Level 3		Total
									Fair Value
	Cash and cash equivalents	$	265,515		$	-	$	-	$	265,515
	Auction rate securities (ARS)		-			-		5,895		5,895
	Other long-term investments		1,701			-		-		1,701
	Total	$	267,216		$	-	$	5,895	$	273,111
	30-Sep-13	Level 1			Level 2		Level 3		Total
									Fair Value
	Cash and cash equivalents	$	226,029		$	-	$	-	$	226,029
	Auction rate securities (ARS)		-			-		7,966		7,966
	Other long-term investments		1,375			-		-		1,375
	Total	$	227,404		$	-	$	7,966	$	235,370
	Our cash and cash equivalents consist of various bank accounts used to support our operations and investments in institutional money-market funds which are traded in active markets. The ARS and other long-term investments are included in other long-term assets on our Consolidated Balance Sheet.  The fair value of our long-term ARS is determined through two discounted cash flow analyses, one using a discount rate based on a market index comprised of tax exempt variable rate demand obligations and one using a discount rate based on the LIBOR swap curve, adding a risk factor to reflect current liquidity issues in the ARS market. Our other long-term investments represent the fair value of investments under the Cabot Microelectronics Supplemental Employee Retirement Plan (SERP), which is a nonqualified supplemental savings plan. The fair value of the investments is determined through quoted market prices within actively traded markets. Although the investments are allocated to individual participants and investment decisions are made solely by those participants, the SERP is a nonqualified plan.  Consequently, the Company owns the assets and the related offsetting liability for disbursement until such time a participant makes a qualifying withdrawal.  The long-term asset was adjusted to $1,701 in the third quarter of fiscal 2014 to reflect its fair value as of June 30, 2014.
	We applied accounting standards regarding the classification and valuation of financial instruments to the valuation of our investment in ARS at June 30, 2014. Our ARS investments at June 30, 2014 consisted of two tax exempt municipal debt securities with a total par value of $5,895. The ARS market began to experience illiquidity in early 2008, and this illiquidity continues. Despite this lack of liquidity, there have been no defaults in payment of the underlying securities and interest income on these holdings continues to be received on scheduled interest payment dates. Our ARS, when purchased, were issued by A-rated municipalities. Although the credit ratings of both municipalities have been downgraded since our original investment, one of the ARS is credit enhanced with bond insurance, and the other, as discussed below in this footnote, has become an obligation of the bond insurer.  Both ARS currently carry a credit rating of AA- by Standard & Poor's.
	Since an active market for ARS does not currently exist, we classify these investments as held-to-maturity and we determine the fair value of these investments using a Level 3 discounted cash flow analysis and also consider other factors such as the reduced liquidity in the ARS market and nature of the insurance backing. Key inputs to our discounted cash flow model include projected cash flows from interest and principal payments and the weighted probabilities of improved liquidity or debt refinancing by the issuer. We also incorporate certain Level 2 market indices into the discounted cash flow analysis, including published rates such as the LIBOR rate, the LIBOR swap curve and a municipal swap index published by the Securities Industry and Financial Markets Association. The following table presents a reconciliation of the activity in fiscal 2014 for fair value measurements using level 3 inputs:
	Balance as of October 1, 2013	$	7,966
	Net sales of ARS		(2,305	)
	Reversal of temporary impairment		234
	Balance as of June 30, 2014	$	5,895
	Based on our fair value assessment, we determined that one ARS continued to be impaired as of September 30, 2013. In November 2011, the municipality that issued our impaired ARS filed for bankruptcy protection. As a result of the approval of the municipality's reorganization plan, and our voting elections, we received 65 % of the par value outstanding, or $2,113, during the quarter ended December 31, 2013, and we reversed the $234 temporary impairment that we previously recorded. We believe that this ARS is no longer impaired as of June 30, 2014 based on: (1) the successful monetization of $2,130 of the par value of the security in accordance with a bankruptcy plan during the nine months ended June 30, 2014; (2) the fact that the bond insurer is now responsible for servicing all future interest and principal payments; (3) the fact that all interest payments have been received; and (4) our intention not to sell the security or be required to sell it until the value is collected in full, which may be at maturity. As of June 30, 2014, this security has a fair value equal to its par value of $1,120. We determined that the fair value of the other ARS was not impaired as of June 30, 2014. See Note 5 for more information on these investments.

INVENTORIES

INVENTORIES	9 Months Ended
	Jun. 30, 2014
INVENTORIES [Abstract]	'
INVENTORIES	'
	3. INVENTORIES
	Inventories consisted of the following:
		30-Jun-14		30-Sep-13
	Raw materials	$	42,258	$	38,004
	Work in process		4,463		5,001
	Finished goods		24,183		20,781
	Total	$	70,904	$	63,786
	The increase in raw material and finished goods inventory is primarily due to higher raw material costs incurred and greater volume levels of certain raw materials maintained in fiscal 2014 in conjunction with certain Company sourcing initiatives.

GOODWILL_AND_OTHER_INTANGIBLE_

GOODWILL AND OTHER INTANGIBLE ASSETS	9 Months Ended
	Jun. 30, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]	'
GOODWILL AND OTHER INTANGIBLE ASSETS	'
	4. GOODWILL AND OTHER INTANGIBLE ASSETS
	Goodwill was $43,882 as of June 30, 2014, and $44,306 as of September 30, 2013.  The decrease in goodwill was due to foreign exchange fluctuations of the New Taiwan dollar.
	The components of other intangible assets are as follows:
		30-Jun-14				30-Sep-13
		Gross Carrying Amount		Accumulated Amortization		Gross Carrying		Accumulated Amortization
						Amount
	Other intangible assets subject to amortization:
	Product technology	$	8,332	$	6,554	$	8,362	$	5,853
	Acquired patents and licenses		8,270		7,456		8,270		7,196
	Trade secrets and know-how		2,550		2,550		2,550		2,550
	Distribution rights, customer lists and other		12,389		8,322		12,496		7,484
	Total other intangible assets subject to amortization		31,541		24,882		31,678		23,083
	Total other intangible assets not subject to amortization*		1,190				1,190
	Total other intangible assets	$	32,731	$	24,882	$	32,868	$	23,083
	*      Total other intangible assets not subject to amortization consist primarily of trade names.
	Amortization expense on our other intangible assets was $601 and $1,870 for the three and nine months ended June 30, 2014, respectively. Amortization expense on our other intangible assets was $654 and $1,973 for the three and nine months ended June 30, 2013, respectively.  Estimated future amortization expense for the five succeeding fiscal years is as follows:
	Fiscal Year	Estimated Amortization Expense
	Remainder of 2014	$	605
	2015		2,413
	2016		1,996
	2017		1,166
	2018		461
	Goodwill and indefinite-lived intangible assets are tested for impairment annually in the fourth quarter of the fiscal year or more frequently if indicators of potential impairment exist, using a fair-value-based approach. The recoverability of goodwill is measured at the reporting unit level, which is defined as either an operating segment or one level below an operating segment. An entity has the option to assess the fair value of a reporting unit either using a qualitative analysis ("step zero") or a discounted cash flow analysis ("step one"). Similarly, an entity has the option to use a step zero or a step one approach to determine the recoverability of indefinite-lived intangible assets. In fiscal 2013, we chose to refresh our step one analysis for both goodwill impairment and for indefinite-lived intangible asset impairment.  Changes in economic and operating conditions that occur after the annual impairment analysis or an interim impairment analysis that impact these assumptions may result in future impairment charges.
	We completed our annual impairment test during our fourth quarter of fiscal 2013 and concluded that no impairment existed. There were no indicators of potential impairment during the nine months ended June 30, 2014, so it was not necessary to perform an impairment review for goodwill and indefinite-lived intangible assets during the first nine months of fiscal year 2014.  There have been no cumulative impairment charges recorded on the goodwill for any of our reporting units.

OTHER_LONGTERM_ASSETS

OTHER LONG-TERM ASSETS	9 Months Ended
	Jun. 30, 2014
OTHER LONG-TERM ASSETS [Abstract]	'
OTHER LONG-TERM ASSETS	'
	5. OTHER LONG-TERM ASSETS
	Other long-term assets consisted of the following:
		30-Jun-14		30-Sep-13
	Auction rate securities	$	5,895	$	7,966
	Other long-term assets		3,092		3,086
	Other long-term investments		1,701		1,375
	Total	$	10,688	$	12,427
	As discussed in Note 2 of this Form 10-Q, the two ARS that we owned as of June 30, 2014 are classified as long-term investments.  One of the securities is credit enhanced with bond insurance and the other is now an obligation of the bond insurer, and all interest payments continue to be received on a timely basis.  Although we believe these securities will ultimately be collected in full, we believe that it is not likely that we will be able to monetize the securities in our next business cycle (which for us is generally one year).  As discussed in Note 2, we received 65 % of the par value outstanding of one of the ARS, or $2,113, during the quarter ended December 31, 2013, and we reversed the $234 pretax reduction ($151 net of tax) in fair value on that ARS that we first recognized in fiscal 2008.  We believe this security is no longer impaired based on: (1) the successful monetization of 65% of the par value of the security in accordance with a bankruptcy plan during the quarter ended December 31, 2013; (2) the fact that the bond insurer is now responsible for servicing all future interest and principal payments; (3) the fact that all interest payments have been received; and (4) our intention not to sell the security nor be required to sell the security until the value is collected in full, which may be at maturity.
	As discussed in Note 2 of this Form 10-Q, we recorded a long-term asset and a corresponding long-term liability of $1,701 representing the fair value of our SERP investments as of June 30, 2014.

ACCRUED_EXPENSES_INCOME_TAXES_

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES	9 Months Ended
	Jun. 30, 2014
ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES [Abstract]	'
ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES	'
	6. ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES
	Accrued expenses, income taxes payable and other current liabilities consisted of the following:
		30-Jun-14		30-Sep-13
	Accrued compensation	$	14,231	$	24,601
	Goods and services received, not yet invoiced		4,067		4,681
	Deferred revenue and customer advances		483		458
	Warranty accrual		240		324
	Income taxes payable		2,773		7,652
	Taxes, other than income taxes		1,164		951
	Other		4,507		1,953
	Total	$	27,465	$	40,620
	The decrease in accrued compensation was primarily due to the payment of our annual incentive bonus program earned in fiscal 2013, partially offset by nine months of accrual under our annual incentive bonus program related to fiscal 2014.  The decrease in income taxes payable was primarily due to tax payments made in foreign jurisdictions.

DEBT

DEBT	9 Months Ended
	Jun. 30, 2014
DEBT [Abstract]	'
DEBT	'
	7. DEBT
	On February 13, 2012, we entered into a credit agreement (the "Credit Agreement") among the Company, as Borrower, Bank of America, N.A., as administrative agent, swing line lender and an L/C issuer, Bank of America Merrill Lynch and J.P. Morgan Securities LLC, as joint lead arrangers and joint book managers, JPMorgan Chase Bank, N.A., as syndication agent, and Wells Fargo Bank, N.A. as documentation agent.  The Credit Agreement provided us with a $175,000 term loan (the "Term Loan"), which we drew on February 27, 2012 to fund approximately half of the special cash dividend we paid to our stockholders on March 1, 2012, and a $100,000 revolving credit facility (the "Revolving Credit Facility"), which remains undrawn, with sub-limits for multicurrency borrowings, letters of credit and swing-line loans.  The Term Loan and the Revolving Credit Facility are referred to as the "Credit Facilities." On June 27, 2014, we entered into an amendment (the "Amendment") to the Credit Agreement, which (i) increased term loan commitments by $17,500, from $157,500 to $175,000, the same level as the original amount under the Credit Agreement at its inception in 2012; (ii) increased the uncommitted accordion feature on the Revolving Credit Facility from $75,000 to $100,000; (iii) extended the expiration date of the Credit Facilities from February 13, 2017 to June 27, 2019; (iv) relaxed the consolidated leverage ratio financial covenant; and (v) revised certain pricing terms and other terms within the Credit Agreement.  On June 27, 2014, we drew the $17,500 of increased term loan commitments, bringing the total outstanding commitments under the Term Loan to $175,000.
	Borrowings under the amended Credit Facilities (other than in respect of swing-line loans) bear interest at a rate per annum equal to the "Applicable Rate" (as defined below) plus, at our option, either (1) a LIBOR rate determined by reference to the cost of funds for deposits in the relevant currency for the interest period relevant to such borrowing or (2) the "Base Rate", which is the highest of (x) the prime rate of Bank of America, N.A., (y) the federal funds rate plus 1/2 of 1.00% and (z) the one-month LIBOR rate plus 1.00%. The current Applicable Rate for borrowings under the Credit Facilities is 1.50%, as amended, with respect to LIBOR borrowings and 0.25% with respect to Base Rate borrowings, with such Applicable Rate subject to adjustment based on our consolidated leverage ratio. Swing-line loans bear interest at the Base Rate plus the Applicable Rate for Base Rate loans under the Revolving Credit Facility.   In addition to paying interest on outstanding principal under the Credit Agreement, we pay a commitment fee to the lenders under the Revolving Credit Facility in respect of the unutilized commitments thereunder.  As amended, the fee ranges from 0.20% to 0.30%, based on our consolidated leverage ratio.  Interest expense and commitment fees are paid according to the relevant interest period and no less frequently than at the end of each calendar quarter. We paid $2,658 in arrangement fees, upfront fees and administration fees in February 2012 and we paid an additional $550 in upfront fees and arrangement fees in June 2014, of which $417 and $1,564 remains in prepaid expenses and other current assets and other long-term assets, respectively, on our Consolidated Balance Sheet as of June 30, 2014.  We must also pay letter of credit fees as necessary.  The Term Loan has periodic scheduled repayments; however, we may voluntarily prepay the Credit Facilities without premium or penalty, subject to customary "breakage" fees and reemployment costs in the case of LIBOR borrowings. All obligations under the Credit Agreement are guaranteed by certain of our existing and future direct and indirect domestic subsidiaries.  The obligations under the Credit Agreement and guarantees of those obligations are secured, subject to certain exceptions, by first priority liens and security interests in the assets of the Company and its domestic subsidiaries.
	The Credit Agreement contains covenants that restrict the ability of the Company and its subsidiaries to take certain actions, including, among other things and subject to certain significant exceptions: creating liens, incurring indebtedness, making investments, engaging in mergers, selling property, paying dividends or amending organizational documents. The Credit Agreement requires us to comply with certain financial ratio maintenance covenants.  As amended, these include a maximum consolidated leverage ratio of 3.00 to 1.00 through December 31, 2015 and a minimum consolidated fixed charge coverage ratio of 1.25 to 1.00.  As amended, the maximum consolidated leverage ratio will decrease to 2.75 to 1.00 from January 1, 2016 through the termination of the Credit Agreement.  As of June 30, 2014, our consolidated leverage ratio was 1.69 to 1.00 and our consolidated fixed charge coverage ratio was 4.81 to 1.00. The Credit Agreement also contains customary affirmative covenants and events of default. We believe we are in compliance with these covenants.
	At June 30, 2014, the fair value of the Term Loan, using level 2 inputs, approximates its carrying value of $175,000 as the loan bears a floating market rate of interest.  As of June 30, 2014, $8,750 of the debt outstanding is classified as short-term.
	Principal repayments of the Term Loan are generally made on the last calendar day of each quarter if that day is considered to be a business day.  As of June 30, 2014, scheduled principal repayments of the Term Loan were as follows:
	Fiscal Year	Principal Repayments
	Remainder of 2014	$	2,188
	2015		8,750
	2016		8,750
	2017		7,656
	2018		14,219
	2019		133,437
	Total	$	175,000

DERIVATIVE_FINANCIAL_INSTRUMEN

DERIVATIVE FINANCIAL INSTRUMENTS	9 Months Ended
	Jun. 30, 2014
DERIVATIVE FINANCIAL INSTRUMENTS [Abstract]	'
DERIVATIVE FINANCIAL INSTRUMENTS	'
	8. DERIVATIVE FINANCIAL INSTRUMENTS
	Periodically we enter into forward foreign exchange contracts in an effort to mitigate the risks associated with currency fluctuations on certain foreign currency balance sheet exposures. Our foreign exchange contracts do not qualify for hedge accounting; therefore, the gains and losses resulting from the impact of currency exchange rate movements on our forward foreign exchange contracts are recognized as other income or expense in the accompanying consolidated income statements in the period in which the exchange rates change.  We do not use derivative financial instruments for trading or speculative purposes.  In addition, all derivatives, whether designated in hedging relationships or not, are required to be recorded on the balance sheet at fair value.  At June 30, 2014, we had forward foreign exchange contracts to either buy or sell Japanese yen and British pound for the purpose of hedging the risk associated with a net transactional exposure in those currencies.
	The fair value of our derivative instruments included in the Consolidated Balance Sheet, which was determined using level 2 inputs, was as follows:
			Asset Derivatives							Liability Derivatives
		Balance Sheet Location	Fair Value at June 30, 2014			Fair Value at September 30, 2013				Fair Value at June 30, 2014				Fair Value at September 30, 2013
	Derivatives not designated as hedging instruments
	Foreign exchange contracts	Prepaid expenses and other current assets		$	172		$	60			$	47			$	-
		Accrued expenses and other current liabilities		$	-		$	-			$	-			$	-
	The following table summarizes the effect of our derivative instruments on our Consolidated Statement of Income for the three and six months ended March 31:
			Gain (Loss) Recognized in Statement of Income
			Three Months Ended							Nine Months Ended
		Statement of Income Location	30-Jun-14			30-Jun-13				30-Jun-14				30-Jun-13
	Derivatives not designated as hedging instruments
	Foreign exchange contracts	Other income, net		$	230		$	(1	)		$	(107	)		$	322

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Jun. 30, 2014
COMMITMENTS AND CONTINGENCIES [Abstract]	'
COMMITMENTS AND CONTINGENCIES	'
	9. COMMITMENTS AND CONTINGENCIES
	LEGAL PROCEEDINGS
	While we are not involved in any legal proceedings that we believe will have a material impact on our consolidated financial position, results of operations or cash flows, we periodically become a party to legal proceedings in the ordinary course of business.
	Refer to Note 16 of "Notes to the Consolidated Financial Statements" in Item 8 of Part II of our annual report on Form 10-K for the fiscal year ended September 30, 2013, for additional information regarding commitments and contingencies.
	PRODUCT WARRANTIES
	We maintain a warranty reserve that reflects management's best estimate of the cost to replace product that does not meet our specifications and customers' performance requirements, and costs related to such replacement. The warranty reserve is based upon a historical product replacement rate, adjusted for any specific known conditions or circumstances.  Additions and deductions to the warranty reserve are recorded in cost of goods sold.  Our warranty reserve activity during the first nine months of fiscal 2014 was as follows:
	Balance as of September 30, 2013	$	324
	Reserve for product warranty during the reporting period		555
	Settlement of warranty		(639	)
	Balance as of June 30, 2014	$	240
	PURCHASE OBLIGATIONS
	Purchase obligations include our take-or-pay arrangements with suppliers, and purchase orders and other obligations entered into in the normal course of business regarding the purchase of goods and services. We operate under a fumed silica supply agreement with Cabot Corporation, our former parent Company, which is not a related party, which requires us to purchase certain minimum quantities of fumed silica each year of the agreement, and to pay a shortfall if we purchase less than the minimum. The agreement became effective as of January 1, 2013 and has an initial term of four years. Purchase obligations as of June 30, 2014 include $81,742 of contractual commitments related to our Cabot Corporation agreement for fumed silica.
	POSTRETIREMENT OBLIGATIONS IN FOREIGN JURISDICTIONS
	As required by local law, we have defined benefit plans covering employees in certain foreign jurisdictions, which are unfunded. Benefit costs, consisting primarily of service costs, are recorded as fringe benefit expense under cost of goods sold and operating expenses in our Consolidated Statements of Income.  The projected benefit obligations and accumulated benefit obligations under all such unfunded plans are updated annually during the fourth quarter of the fiscal year. Benefit payments under all such unfunded plans to be paid over the next 10 years are expected to be immaterial. For more information regarding these plans, refer to Note 16 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our annual report on Form 10-K for the fiscal year ended September 30, 2013.

SHAREBASED_COMPENSATION_PLANS

SHARE-BASED COMPENSATION PLANS	9 Months Ended
	Jun. 30, 2014
SHARE-BASED COMPENSATION PLANS [Abstract]	'
SHARE-BASED COMPENSATION PLANS	'
	10. SHARE-BASED COMPENSATION PLANS
	We issue share-based awards under the following programs: our Cabot Microelectronics Corporation 2012 Omnibus Incentive Plan (OIP), our Cabot Microelectronics Corporation 2007 Employee Stock Purchase Plan, as Amended and Restated January 1, 2010 (ESPP), and, pursuant to the OIP, our Directors' Deferred Compensation Plan, as amended September 23, 2008 (DDCP), and our 2001 Executive Officer Deposit Share Program (DSP). Prior to March 2012, when our stockholders approved the OIP, we issued share-based payments under our Second Amended and Restated Cabot Microelectronics Corporation 2000 Equity Incentive Plan, as amended and restated September 23, 2008 (EIP); our ESPP, and, pursuant to the EIP, the DDCP and DSP. For additional information regarding these programs, refer to Note 11 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our annual report on Form 10-K for the fiscal year ended September 30, 2013. Other than the ESPP, all share-based payments granted beginning March 6, 2012 are made from the OIP, and the EIP is no longer available for any awards.
	We record share-based compensation expense for all share-based awards, including stock option grants, restricted stock and restricted stock unit awards and employee stock purchase plan purchases.  We calculate share-based compensation expense using the straight-line approach based on awards ultimately expected to vest, which requires the use of an estimated forfeiture rate.  Our estimated forfeiture rate is primarily based on historical experience, but may be revised in future periods if actual forfeitures differ from the estimate. We use the Black-Scholes option-pricing model to estimate the grant date fair value of our stock options and employee stock purchase plan purchases.  This model requires the input of highly subjective assumptions, including the price volatility of the underlying stock, the expected term of our stock options and the risk-free interest rate.  We estimate the expected volatility of our stock options based on a combination of our stock's historical volatility and the implied volatilities from actively-traded options on our stock. We calculate the expected term of our stock options using historical stock option exercise data, and we add a slight premium to this expected term for employees who meet the definition of retirement eligible pursuant to their grants during the contractual term of the grant. The risk-free rate is derived from the U.S. Treasury yield curve in effect at the time of grant.
	Share-based compensation expense for the three and nine months ended June 30, 2014, and 2013, was as follows:
		Three Months Ended June 30,						Nine Months Ended June 30,
		2014			2013			2014			2013
	Cost of goods sold	$	462		$	385		$	1,391		$	1,300
	Research, development and technical		378			313			1,096			989
	Selling and marketing		318			326			978			1,036
	General and administrative		1,948			1,990			7,432			6,992
	Total share-based compensation expense		3,106			3,014			10,897			10,317
	Tax benefit		(1,009	)		(1,010	)		(3,694	)		(3,541	)
	Total share-based compensation expense, net of tax	$	2,097		$	2,004		$	7,203		$	6,776
	Our non-employee directors received annual equity awards in March 2014, pursuant to the OIP. The award agreements provide for immediate vesting of the award at the time of termination of service for any reason other than by reason of Cause, Death, Disability or a Change in Control, as defined in the OIP, if at such time the non-employee director has completed an equivalent of at least two full terms as a director of the Company, as defined in the Company's bylaws.  Seven of the Company's eight non-employee directors had completed at least two full terms of service as of the date of the March 2014 award.  Consequently, the requisite service period for the award has already been satisfied and we recorded the fair value of $1,325 of the awards to these seven directors to share-based compensation expense in the fiscal quarter ended March 31, 2014 rather than recording that expense over the one-year vesting period stated in the award agreement, as is done for the other non-employee director.
	For additional information regarding the estimation of fair value, refer to Note 11 of "Notes to the Consolidated Financial Statements" included in Item 8 of Part II of our annual report on Form 10-K for the fiscal year ended September 30, 2013.

OTHER_INCOME_EXPENSE_NET

OTHER INCOME (EXPENSE), NET	9 Months Ended
	Jun. 30, 2014
OTHER INCOME (EXPENSE), NET [Abstract]	'
OTHER INCOME (EXPENSE), NET	'
	11. OTHER INCOME (EXPENSE), NET
	Other income (expense), net, consisted of the following:
		Three Months Ended June 30,					Nine Months Ended June 30,
		2014			2013		2014		2013
	Interest income	$	91		$	44	$	170	$	122
	Other income (expense)		(223	)		204		418		1,443
	Total other income (expense), net	$	(132	)	$	248	$	588	$	1,565
	Other income (expense) primarily represents the gains and losses recorded on transactions denominated in foreign currencies. The decrease in other income was primarily due to the impact of foreign currency fluctuations on monetary assets and liabilities denominated in currencies other than the functional currency, net of the gains and losses incurred on forward foreign exchange contracts discussed in Note 8 of this Form 10-Q.

INCOME_TAXES

INCOME TAXES	9 Months Ended
	Jun. 30, 2014
INCOME TAXES [Abstract]	'
INCOME TAXES	'
	12. INCOME TAXES
	Our effective income tax rate was 24.1 % and 25.9 % for the three and nine months ended June 30, 2014 compared to a 24.4 % and 28.2 % effective income tax rate for the three and nine months ended June 30, 2013.  The effective income tax rate for the comparable periods of fiscal 2013 has been revised downward from 28.1% and 33.0%, as originally presented, to reflect the correction on non-material period period adjustments discussed in Note 1 under the heading "Revision of Prior Period Amounts".  The decrease in the effective tax rate during the first nine months of fiscal 2014 was primarily due to lower income tax expense on foreign earnings resulting from our election to permanently reinvest the earnings of our foreign subsidiaries.  The Company was awarded a tax holiday in South Korea in conjunction with our investment in research, development and manufacturing facilities there.  Subject to certain conditions, which we believe we have met, this arrangement allows for a 0 % tax rate in fiscal years 2013, 2014 and 2015, and a tax at 50 % of the local statutory rate in effect for fiscal years 2016 and 2017.  This tax holiday reduced our income tax provision by approximately $2,857 in the first nine months of fiscal 2014.

EARNINGS_PER_SHARE

EARNINGS PER SHARE	9 Months Ended
	Jun. 30, 2014
EARNINGS PER SHARE [Abstract]	'
EARNINGS PER SHARE	'
	13. EARNINGS PER SHARE
	Basic earnings per share (EPS) is calculated by dividing net income available to common stockholders by the weighted-average number of common shares outstanding during the period, excluding the effects of unvested restricted stock awards with a right to receive non-forfeitable dividends, which are considered participating securities as prescribed by the two-class method under ASC 260. Diluted EPS is calculated in a similar manner, but the weighted-average number of common shares outstanding during the period is increased to include the weighted-average dilutive effect of "in-the-money" stock options and unvested restricted stock shares using the treasury stock method.
	The standards of accounting for earnings per share require companies to provide a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations. Basic and diluted earnings per share were calculated as follows:
		Three Months Ended June 30,						Nine Months Ended June 30,
		2014			2013			2014			2013
	Numerator:
	Net income	$	13,302		$	16,294		$	34,705		$	37,103
	Less: income attributable to participating securities		(176	)		(216	)		(311	)		(365	)
	Earnings available to common shares	$	13,126		$	16,078		$	34,394		$	36,738
	Denominator:
	Weighted average common shares		23,752,770			22,951,408			23,768,858			22,897,320
	(Denominator for basic calculation)
	Weighted average effect of dilutive securities:
	Share-based compensation		860,722			787,951			935,511			799,909
	Diluted weighted average common shares		24,613,492			23,739,359			24,704,369			23,697,229
	(Denominator for diluted calculation)
	Earnings per share:
	Basic	$	0.55		$	0.7		$	1.45		$	1.6
	Diluted	$	0.53		$	0.68		$	1.39		$	1.55
	For the three months ended June 30, 2014 and 2013, approximately 0.5 million and 1.5 million shares, respectively, attributable to outstanding stock options were excluded from the calculation of diluted earnings per share because the exercise price of the options was greater than the average market price of our common stock and, therefore, their inclusion would have been anti-dilutive.
	For the nine months ended June 30, 2014 and 2013, approximately 0.5 million and 1.6 million shares, respectively, attributable to outstanding stock options were excluded from the calculation of diluted earnings per share because the exercise price of the options was greater than the average market price of our common stock and, therefore, their inclusion would have been anti-dilutive.

FINANCIAL_INFORMATION_BY_INDUS

FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE	9 Months Ended
	Jun. 30, 2014
FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE [Abstract]	'
FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE	'
	14. FINANCIAL INFORMATION BY INDUSTRY SEGMENT AND PRODUCT LINE
	We operate predominantly in one industry segment – the development, manufacture, and sale of CMP consumables.
	Revenue generated by product line for the three and nine months ended June 30, 2014, and 2013, was as follows:
		Three Months Ended June 30,				Nine Months Ended June 30,
	Revenue:	2014		2013		2014		2013
	Tungsten slurries	$	42,170	$	38,634	$	117,098	$	116,159
	Dielectric slurries		29,651		30,581		88,718		90,673
	Other Metals slurries		19,641		20,106		54,782		55,147
	Polishing pads		8,764		8,451		23,934		24,317
	Data storage slurries		4,225		5,270		13,693		15,756
	Engineered Surface Finishes		3,907		6,926		10,104		14,813
	Total revenue	$	108,358	$	109,968	$	308,329	$	316,865
	In past years, we have referred to "Other Metals slurries" as "Copper slurries", which included slurries for polishing copper, barrier and aluminum. To more accurately reflect changes within this product family, and in particular, growth in revenue from slurries for polishing aluminum, we now refer to this product family as "Other Metals slurries".

NEW_ACCOUNTING_PRONOUNCEMENTS

NEW ACCOUNTING PRONOUNCEMENTS	9 Months Ended
	Jun. 30, 2014
NEW ACCOUNTING PRONOUNCEMENTS [Abstract]	'
NEW ACCOUNTING PRONOUNCEMENTS	'
	15. NEW ACCOUNTING PRONOUNCEMENTS
	In July 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2013-11, "Income Taxes (Topic 740) – Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists" (ASU 2013-11).  The provisions of ASU 2013-11 require an entity to present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward when the related deferred tax asset is available to be utilized.  ASU 2013-11 is effective for us beginning October 1, 2014.  We do not expect the adoption of ASU 2013-11 will have a material impact on our financial statements.
	In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers" (Topic 606), an updated standard on revenue recognition.  ASU 2014-09 provides enhancements to how revenue is reported and improves comparability in the financial statements of companies reporting using IFRS and US GAAP.  The core principle of the new standard is for companies to recognize revenue for goods or services in amounts that reflect the consideration to which the company expects to be entitled in exchange for those goods or services.  The new standard is intended to enhance disclosures about revenue, provide guidance for transactions that were not previously addressed comprehensively, such as service revenue and contract modifications, and improve guidance for multiple-element arrangements.  ASU 2014-09 will be effective for us beginning October 1, 2017 and may be applied on a full retrospective or modified retrospective approach.  We are evaluating the impact of implementation of this standard on our financial statements.
	In June 2014, the FASB issued ASU No. 2014-14, "Accounting for Share-Based Payments When the Terms of an Award Provide that a Performance Target Could be Achieved after the Requisite Service Period" (Topic 718).  ASU 2014-14 requires that a performance target that affects vesting and that could be achieved after the requisite service period be treated as a performance condition.  As such, the performance target should not be reflected in estimating the grant date fair value of an award, and compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved.  The compensation cost should represent the amount attributable to the periods for which the requisite service has been rendered.  ASU 2014-09 will be effective for us beginning October 1, 2016 and may be applied on a prospective or retrospective basis.  We do not expect the implementation of this standard to have a material effect on our financial statements as we have not granted any awards with a performance condition.

BACKGROUND_AND_BASIS_OF_PRESEN1

BACKGROUND AND BASIS OF PRESENTATION (Tables)	9 Months Ended
	Jun. 30, 2014
BACKGROUND AND BASIS OF PRESENTATION [Abstract]	'
Revision of Prior Period Amounts	'
	The following tables summarize the effects of the revisions to the financial statements for the comparative periods of fiscal 2013 (in thousands, except per share data):
	CONSOLIDATED STATEMENTS OF INCOME
		Three Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Income before income taxes	$	21,555		$	-		$	21,555
	Provision for income taxes		6,062			(801	)		5,261
	Net income		15,493			801			16,294
	Basic earnings per share	$	0.68		$	0.02		$	0.7
	Weighted average diluted shares outstanding		23,776			(37	)		23,739
	Diluted earnings per share	$	0.65		$	0.03		$	0.68
		Nine Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Income before income taxes	$	51,646		$	-		$	51,646
	Provision for income taxes		17,030			(2,487	)		14,543
	Net income		34,616			2,487			37,103
	Basic earnings per share	$	1.51		$	0.09		$	1.6
	Weighted average diluted shares outstanding		23,729			(32	)		23,697
	Diluted earnings per share	$	1.46		$	0.09		$	1.55
	CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
		Three Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Net income	$	15,493		$	801		$	16,294
	Other comprehensive income (loss), net of tax		(4,077	)		-			(4,077	)
	Comprehensive income	$	11,416		$	801		$	12,217
		Nine Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Net income	$	34,616		$	2,487		$	37,103
	Other comprehensive income (loss), net of tax		(15,828	)		-			(15,828	)
	Comprehensive income	$	18,788		$	2,487		$	21,275
	CONSOLIDATED BALANCE SHEET
		30-Sep-13
		As			Adjustment			As
		Originally						Revised
		Reported
	Prepaid expenses and other current assets	$	13,598		$	(2,914	)	$	10,684
	Total current assets		365,712			(2,914	)		362,798
	Total assets		554,506			(2,914	)		551,592
	Accrued expenses, income taxes payable and other current liabilities		39,899			721			40,620
	Total current liabilities		67,500			721			68,221
	Total liabilities		227,429			721			228,150
	Retained earnings		180,826			(3,635	)		177,191
	Total stockholders' equity		327,077			(3,635	)		323,442
	Total liabilities and stockholders' equity	$	554,506		$	(2,914	)	$	551,592
	CONSOLIDATED STATEMENT OF CASH FLOWS
		Nine Months Ended June 30, 2013
		As			Adjustment			As
		Originally						Revised
		Reported
	Net income	$	34,616		$	2,487		$	37,103
	Deferred income tax expense (benefit)		912			(1,686	)		(774	)
	Change in accrued expenses, income taxes payable and other current liabilities		4,856			(801	)		4,055
	Net cash provided by operating activities	$	53,451		$	-		$	53,451

FAIR_VALUE_OF_FINANCIAL_INSTRU1

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	9 Months Ended
	Jun. 30, 2014
FAIR VALUE OF FINANCIAL INSTRUMENTS [Abstract]	'
Schedule of Fair Value of Financial Instruments	'
	The following table presents financial instruments, other than long-term debt, that we measured at fair value on a recurring basis at June 30, 2014 and September 30, 2013. See Note 7 for a detailed discussion of our long-term debt. We have chosen to not measure any of our other financial instruments at fair value as we believe their carrying value approximates their fair value. We have classified the following assets in accordance with the fair value hierarchy set forth in the applicable standards. In instances where the inputs used to measure the fair value of an asset fall into more than one level of the hierarchy, we have classified them based on the lowest level input that is significant to the determination of the fair value.
	30-Jun-14	Level 1			Level 2		Level 3		Total
									Fair Value
	Cash and cash equivalents	$	265,515		$	-	$	-	$	265,515
	Auction rate securities (ARS)		-			-		5,895		5,895
	Other long-term investments		1,701			-		-		1,701
	Total	$	267,216		$	-	$	5,895	$	273,111
	30-Sep-13	Level 1			Level 2		Level 3		Total
									Fair Value
	Cash and cash equivalents	$	226,029		$	-	$	-	$	226,029
	Auction rate securities (ARS)		-			-		7,966		7,966
	Other long-term investments		1,375			-		-		1,375
	Total	$	227,404		$	-	$	7,966	$	235,370
Schedule of Auction Rate Securities (ARS) Activity	'
	Since an active market for ARS does not currently exist, we classify these investments as held-to-maturity and we determine the fair value of these investments using a Level 3 discounted cash flow analysis and also consider other factors such as the reduced liquidity in the ARS market and nature of the insurance backing. Key inputs to our discounted cash flow model include projected cash flows from interest and principal payments and the weighted probabilities of improved liquidity or debt refinancing by the issuer. We also incorporate certain Level 2 market indices into the discounted cash flow analysis, including published rates such as the LIBOR rate, the LIBOR swap curve and a municipal swap index published by the Securities Industry and Financial Markets Association. The following table presents a reconciliation of the activity in fiscal 2014 for fair value measurements using level 3 inputs:
	Balance as of October 1, 2013	$	7,966
	Net sales of ARS		(2,305	)
	Reversal of temporary impairment		234
	Balance as of June 30, 2014	$	5,895

INVENTORIES_Tables

INVENTORIES (Tables)	9 Months Ended
	Jun. 30, 2014
INVENTORIES [Abstract]	'
Schedule of inventories	'
	Inventories consisted of the following:
		30-Jun-14		30-Sep-13
	Raw materials	$	42,258	$	38,004
	Work in process		4,463		5,001
	Finished goods		24,183		20,781
	Total	$	70,904	$	63,786

GOODWILL_AND_OTHER_INTANGIBLE_1

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	9 Months Ended
	Jun. 30, 2014
GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]	'
Components of other intangible assets	'
	The components of other intangible assets are as follows:
		30-Jun-14				30-Sep-13
		Gross Carrying Amount		Accumulated Amortization		Gross Carrying		Accumulated Amortization
						Amount
	Other intangible assets subject to amortization:
	Product technology	$	8,332	$	6,554	$	8,362	$	5,853
	Acquired patents and licenses		8,270		7,456		8,270		7,196
	Trade secrets and know-how		2,550		2,550		2,550		2,550
	Distribution rights, customer lists and other		12,389		8,322		12,496		7,484
	Total other intangible assets subject to amortization		31,541		24,882		31,678		23,083
	Total other intangible assets not subject to amortization*		1,190				1,190
	Total other intangible assets	$	32,731	$	24,882	$	32,868	$	23,083
	*      Total other intangible assets not subject to amortization consist primarily of trade names.
Estimated future amortization expense for the succeeding five fiscal years	'
	Amortization expense on our other intangible assets was $601 and $1,870 for the three and nine months ended June 30, 2014, respectively. Amortization expense on our other intangible assets was $654 and $1,973 for the three and nine months ended June 30, 2013, respectively.  Estimated future amortization expense for the five succeeding fiscal years is as follows:
	Fiscal Year	Estimated Amortization Expense
	Remainder of 2014	$	605
	2015		2,413
	2016		1,996
	2017		1,166
	2018		461

OTHER_LONGTERM_ASSETS_Tables

OTHER LONG-TERM ASSETS (Tables)	9 Months Ended
	Jun. 30, 2014
OTHER LONG-TERM ASSETS [Abstract]	'
Schedule of other long term assets	'
	Other long-term assets consisted of the following:
		30-Jun-14		30-Sep-13
	Auction rate securities	$	5,895	$	7,966
	Other long-term assets		3,092		3,086
	Other long-term investments		1,701		1,375
	Total	$	10,688	$	12,427

ACCRUED_EXPENSES_INCOME_TAXES_1

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES (Tables)	9 Months Ended
	Jun. 30, 2014
ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES [Abstract]	'
Schedule of accrued expenses, income taxes payable and other current liabilities	'
	Accrued expenses, income taxes payable and other current liabilities consisted of the following:
		30-Jun-14		30-Sep-13
	Accrued compensation	$	14,231	$	24,601
	Goods and services received, not yet invoiced		4,067		4,681
	Deferred revenue and customer advances		483		458
	Warranty accrual		240		324
	Income taxes payable		2,773		7,652
	Taxes, other than income taxes		1,164		951
	Other		4,507		1,953
	Total	$	27,465	$	40,620

DEBT_Tables

DEBT (Tables)	9 Months Ended
	Jun. 30, 2014
DEBT [Abstract]	'
Schedule of Maturities of Long-term Debt	'
	Principal repayments of the Term Loan are generally made on the last calendar day of each quarter if that day is considered to be a business day.  As of June 30, 2014, scheduled principal repayments of the Term Loan were as follows:
	Fiscal Year	Principal Repayments
	Remainder of 2014	$	2,188
	2015		8,750
	2016		8,750
	2017		7,656
	2018		14,219
	2019		133,437
	Total	$	175,000

DERIVATIVE_FINANCIAL_INSTRUMEN1

DERIVATIVE FINANCIAL INSTRUMENTS (Tables)	9 Months Ended
	Jun. 30, 2014
DERIVATIVE FINANCIAL INSTRUMENTS [Abstract]	'
Schedule of Fair Value of Derivative Instruments in the Consolidated Balance Sheet	'
	The fair value of our derivative instruments included in the Consolidated Balance Sheet, which was determined using level 2 inputs, was as follows:
			Asset Derivatives							Liability Derivatives
		Balance Sheet Location	Fair Value at June 30, 2014			Fair Value at September 30, 2013				Fair Value at June 30, 2014				Fair Value at September 30, 2013
	Derivatives not designated as hedging instruments
	Foreign exchange contracts	Prepaid expenses and other current assets		$	172		$	60			$	47			$	-
		Accrued expenses and other current liabilities		$	-		$	-			$	-			$	-
Schedule of the Effect of Derivative Instruments on the Consolidated Statement of Income	'
	The following table summarizes the effect of our derivative instruments on our Consolidated Statement of Income for the three and six months ended March 31:
			Gain (Loss) Recognized in Statement of Income
			Three Months Ended							Nine Months Ended
		Statement of Income Location	30-Jun-14			30-Jun-13				30-Jun-14				30-Jun-13
	Derivatives not designated as hedging instruments
	Foreign exchange contracts	Other income, net		$	230		$	(1	)		$	(107	)		$	322

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	9 Months Ended
	Jun. 30, 2014
COMMITMENTS AND CONTINGENCIES [Abstract]	'
Schedule of product warranty reserve activity	'
	We maintain a warranty reserve that reflects management's best estimate of the cost to replace product that does not meet our specifications and customers' performance requirements, and costs related to such replacement. The warranty reserve is based upon a historical product replacement rate, adjusted for any specific known conditions or circumstances.  Additions and deductions to the warranty reserve are recorded in cost of goods sold.  Our warranty reserve activity during the first nine months of fiscal 2014 was as follows:
	Balance as of September 30, 2013	$	324
	Reserve for product warranty during the reporting period		555
	Settlement of warranty		(639	)
	Balance as of June 30, 2014	$	240

SHAREBASED_COMPENSATION_PLANS_

SHARE-BASED COMPENSATION PLANS (Tables)	9 Months Ended
	Jun. 30, 2014
SHARE-BASED COMPENSATION PLANS [Abstract]	'
Share based compensation expense	'
	Share-based compensation expense for the three and nine months ended June 30, 2014, and 2013, was as follows:
		Three Months Ended June 30,						Nine Months Ended June 30,
		2014			2013			2014			2013
	Cost of goods sold	$	462		$	385		$	1,391		$	1,300
	Research, development and technical		378			313			1,096			989
	Selling and marketing		318			326			978			1,036
	General and administrative		1,948			1,990			7,432			6,992
	Total share-based compensation expense		3,106			3,014			10,897			10,317
	Tax benefit		(1,009	)		(1,010	)		(3,694	)		(3,541	)
	Total share-based compensation expense, net of tax	$	2,097		$	2,004		$	7,203		$	6,776

OTHER_INCOME_EXPENSE_NET_Table

OTHER INCOME (EXPENSE), NET (Tables)	9 Months Ended
	Jun. 30, 2014
OTHER INCOME (EXPENSE), NET [Abstract]	'
Other income (expense), net	'
	Other income (expense), net, consisted of the following:
		Three Months Ended June 30,					Nine Months Ended June 30,
		2014			2013		2014		2013
	Interest income	$	91		$	44	$	170	$	122
	Other income (expense)		(223	)		204		418		1,443
	Total other income (expense), net	$	(132	)	$	248	$	588	$	1,565

EARNINGS_PER_SHARE_Tables

EARNINGS PER SHARE (Tables)	9 Months Ended
	Jun. 30, 2014
EARNINGS PER SHARE [Abstract]	'
Earnings Per Share	'
	The standards of accounting for earnings per share require companies to provide a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations. Basic and diluted earnings per share were calculated as follows:
		Three Months Ended June 30,						Nine Months Ended June 30,
		2014			2013			2014			2013
	Numerator:
	Net income	$	13,302		$	16,294		$	34,705		$	37,103
	Less: income attributable to participating securities		(176	)		(216	)		(311	)		(365	)
	Earnings available to common shares	$	13,126		$	16,078		$	34,394		$	36,738
	Denominator:
	Weighted average common shares		23,752,770			22,951,408			23,768,858			22,897,320
	(Denominator for basic calculation)
	Weighted average effect of dilutive securities:
	Share-based compensation		860,722			787,951			935,511			799,909
	Diluted weighted average common shares		24,613,492			23,739,359			24,704,369			23,697,229
	(Denominator for diluted calculation)
	Earnings per share:
	Basic	$	0.55		$	0.7		$	1.45		$	1.6
	Diluted	$	0.53		$	0.68		$	1.39		$	1.55

FINANCIAL_INFORMATION_BY_INDUS1

FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE (Tables)	9 Months Ended
	Jun. 30, 2014
FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE [Abstract]	'
Schedule of revenue by product line	'
	Revenue generated by product line for the three and nine months ended June 30, 2014, and 2013, was as follows:
		Three Months Ended June 30,				Nine Months Ended June 30,
	Revenue:	2014		2013		2014		2013
	Tungsten slurries	$	42,170	$	38,634	$	117,098	$	116,159
	Dielectric slurries		29,651		30,581		88,718		90,673
	Other Metals slurries		19,641		20,106		54,782		55,147
	Polishing pads		8,764		8,451		23,934		24,317
	Data storage slurries		4,225		5,270		13,693		15,756
	Engineered Surface Finishes		3,907		6,926		10,104		14,813
	Total revenue	$	108,358	$	109,968	$	308,329	$	316,865

BACKGROUND_AND_BASIS_OF_PRESEN2

BACKGROUND AND BASIS OF PRESENTATION (Details) (USD $)	3 Months Ended			9 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
		BasisPoint		BasisPoint
CONSOLIDATED STATEMENTS OF INCOME [Abstract]	'	'	'	'	'	'
Income before income taxes	$17,525	'	$21,555	$46,854	$51,646	'
Provision for income taxes	4,223	'	5,261	12,149	14,543	'
Net income	13,302	'	16,294	34,705	37,103	'
Basic earnings per share (in dollars per share)	$0.55	'	$0.70	$1.45	$1.60	'
Weighted average diluted shares outstanding (in shares)	24,613,492	'	23,739,359	24,704,369	23,697,229	'
Diluted earnings per share (in dollars per share)	$0.53	'	$0.68	$1.39	$1.55	'
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]	'	'	'	'	'	'
Net income	13,302	'	16,294	34,705	37,103	'
Other comprehensive income (loss), net of tax	3,644	'	-4,077	-1,417	-15,828	'
Comprehensive income	16,946	'	12,217	33,288	21,275	'
CONSOLIDATED BALANCE SHEETS [Abstract]	'	'	'	'	'	'
Prepaid expenses and other current assets	12,917	'	'	12,917	'	10,684
Total current assets	412,831	'	'	412,831	'	362,798
Total assets	589,978	'	'	589,978	'	551,592
Accrued expenses, income taxes payable and other current liabilities	27,465	'	'	27,465	'	40,620
Total current liabilities	48,643	'	'	48,643	'	68,221
Total liabilities	225,436	'	'	225,436	'	228,150
Retained earnings	211,896	'	'	211,896	'	177,191
Total stockholders' equity	364,542	'	'	364,542	'	323,442
Total liabilities and stockholders' equity	589,978	'	'	589,978	'	551,592
CONSOLIDATED STATEMENTS OF CASH FLOWS [Abstract]	'	'	'	'	'	'
Net income	13,302	'	16,294	34,705	37,103	'
Deferred income tax expense (benefit)	'	'	'	641	-774	'
Change in accrued expenses, income taxes payable and other liabilities	'	'	'	-12,564	4,055	'
Net cash provided by operating activities	'	'	'	36,736	53,451	'
Results of Operations [Abstract]	'	'	'	'	'	'
Production Related Impairments or Charges, Total	'	'	'	2,111	'	'
Asset impairment charge to cost of goods sold, net of tax	'	'	'	1,475	'	'
Basis point reduction in gross profit percentage as a result of an asset impairment charge	'	210	'	70	'	'
Diluted earnings per share effect of asset impairment charge	'	'	'	$0.06	'	'
As Originally Reported [Member]	'	'	'	'	'	'
CONSOLIDATED STATEMENTS OF INCOME [Abstract]	'	'	'	'	'	'
Income before income taxes	'	'	21,555	'	51,646	'
Provision for income taxes	'	'	6,062	'	17,030	'
Net income	'	'	15,493	'	34,616	'
Basic earnings per share (in dollars per share)	'	'	$0.68	'	$1.51	'
Weighted average diluted shares outstanding (in shares)	'	'	23,776,000	'	23,729,000	'
Diluted earnings per share (in dollars per share)	'	'	$0.65	'	$1.46	'
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]	'	'	'	'	'	'
Net income	'	'	15,493	'	34,616	'
Other comprehensive income (loss), net of tax	'	'	-4,077	'	-15,828	'
Comprehensive income	'	'	11,416	'	18,788	'
CONSOLIDATED BALANCE SHEETS [Abstract]	'	'	'	'	'	'
Prepaid expenses and other current assets	'	'	'	'	'	13,598
Total current assets	'	'	'	'	'	365,712
Total assets	'	'	'	'	'	554,506
Accrued expenses, income taxes payable and other current liabilities	'	'	'	'	'	39,899
Total current liabilities	'	'	'	'	'	67,500
Total liabilities	'	'	'	'	'	227,429
Retained earnings	'	'	'	'	'	180,826
Total stockholders' equity	'	'	'	'	'	327,077
Total liabilities and stockholders' equity	'	'	'	'	'	554,506
CONSOLIDATED STATEMENTS OF CASH FLOWS [Abstract]	'	'	'	'	'	'
Net income	'	'	15,493	'	34,616	'
Deferred income tax expense (benefit)	'	'	'	'	912	'
Change in accrued expenses, income taxes payable and other liabilities	'	'	'	'	4,856	'
Net cash provided by operating activities	'	'	'	'	53,451	'
Adjustment [Member]	'	'	'	'	'	'
CONSOLIDATED STATEMENTS OF INCOME [Abstract]	'	'	'	'	'	'
Income before income taxes	'	'	0	'	0	'
Provision for income taxes	'	'	-801	'	-2,487	'
Net income	'	'	801	'	2,487	'
Basic earnings per share (in dollars per share)	'	'	$0.02	'	$0.09	'
Weighted average diluted shares outstanding (in shares)	'	'	-37,000	'	-32,000	'
Diluted earnings per share (in dollars per share)	'	'	$0.03	'	$0.09	'
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]	'	'	'	'	'	'
Net income	'	'	801	'	2,487	'
Other comprehensive income (loss), net of tax	'	'	0	'	0	'
Comprehensive income	'	'	801	'	2,487	'
CONSOLIDATED BALANCE SHEETS [Abstract]	'	'	'	'	'	'
Prepaid expenses and other current assets	'	'	'	'	'	-2,914
Total current assets	'	'	'	'	'	-2,914
Total assets	'	'	'	'	'	-2,914
Accrued expenses, income taxes payable and other current liabilities	'	'	'	'	'	721
Total current liabilities	'	'	'	'	'	721
Total liabilities	'	'	'	'	'	721
Retained earnings	'	'	'	'	'	-3,635
Total stockholders' equity	'	'	'	'	'	-3,635
Total liabilities and stockholders' equity	'	'	'	'	'	-2,914
CONSOLIDATED STATEMENTS OF CASH FLOWS [Abstract]	'	'	'	'	'	'
Net income	'	'	801	'	2,487	'
Deferred income tax expense (benefit)	'	'	'	'	-1,686	'
Change in accrued expenses, income taxes payable and other liabilities	'	'	'	'	-801	'
Net cash provided by operating activities	'	'	'	'	$0	'

FAIR_VALUE_OF_FINANCIAL_INSTRU2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Jun. 30, 2014
		Security
FAIR VALUE OF FINANCIAL INSTRUMENTS [Abstract]	'	'
Other long-term investments, Supplemental Employee Retirement Plan (SERP)	'	$1,701
Corresponding SERP liability	'	1,701
Number of tax exempt municipal debt securities	'	2
Auction rate securities (ARS) par value	'	5,895
Fair value of formerly impaired security	'	1,120
Par value of formerly impaired security	'	1,120
Percentage of par value received from auction rate security settlement	65.00%	'
Monetized par value of impaired security	$2,113	$2,130

FAIR_VALUE_OF_FINANCIAL_INSTRU3

FAIR VALUE OF FINANCIAL INSTRUMENTS, Schedule of Fair Value of Financial Instruments (Details) (Fair Value, Measurements, Recurring [Member], USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and cash equivalents	$265,515	$226,029
Auction rate securities (ARS)	5,895	7,966
Other long-term investments	1,701	1,375
Total	273,111	235,370
Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and cash equivalents	265,515	226,029
Auction rate securities (ARS)	0	0
Other long-term investments	1,701	1,375
Total	267,216	227,404
Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and cash equivalents	0	0
Auction rate securities (ARS)	0	0
Other long-term investments	0	0
Total	0	0
Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash and cash equivalents	0	0
Auction rate securities (ARS)	5,895	7,966
Other long-term investments	0	0
Total	$5,895	$7,966

FAIR_VALUE_OF_FINANCIAL_INSTRU4

FAIR VALUE OF FINANCIAL INSTRUMENTS, Schedule of Auction Rate Securities (ARS) Activity (Details) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Jun. 30, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance as of October 1, 2013	$7,966	$7,966
Net sales of ARS	'	-2,305
Reversal of temporary impairment	234	234
Balance as of June 30, 2014	'	$5,895

INVENTORIES_Details

INVENTORIES (Details) (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
INVENTORIES [Abstract]	'	'
Raw materials	$42,258	$38,004
Work in process	4,463	5,001
Finished goods	24,183	20,781
Total	$70,904	$63,786

GOODWILL_AND_OTHER_INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
Goodwill [Roll Forward]	'	'	'	'	'
Beginning Balance	'	'	$44,306	'	'
Ending Balance	43,882	'	43,882	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Gross Carrying Amount subject to amortization	31,541	'	31,541	'	31,678
Accumulated Amortization	24,882	'	24,882	'	23,083
Other intangible assets [Abstract]	'	'	'	'	'
Amortization expense	601	654	1,870	1,973	'
Indefinite-lived Intangible Assets by Major Class [Line Items]	'	'	'	'	'
Gross Carrying Amount not subject to amortization	1,190	'	1,190	'	1,190
Estimated future amortization expense [Abstract]	'	'	'	'	'
Remainder of 2014	605	'	605	'	'
2015	2,413	'	2,413	'	'
2016	1,996	'	1,996	'	'
2017	1,166	'	1,166	'	'
2018	461	'	461	'	'
Total other intangible assets, gross carrying amount	32,731	'	32,731	'	32,868
Product Technology [Member]	'	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Gross Carrying Amount subject to amortization	8,332	'	8,332	'	8,362
Accumulated Amortization	6,554	'	6,554	'	5,853
Acquired Patents and Licenses [Member]	'	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Gross Carrying Amount subject to amortization	8,270	'	8,270	'	8,270
Accumulated Amortization	7,456	'	7,456	'	7,196
Trade Secrets [Member]	'	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Gross Carrying Amount subject to amortization	2,550	'	2,550	'	2,550
Accumulated Amortization	2,550	'	2,550	'	2,550
Distribution Rights, Customer relationships, and Other [Member]	'	'	'	'	'
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Gross Carrying Amount subject to amortization	12,389	'	12,389	'	12,496
Accumulated Amortization	$8,322	'	$8,322	'	$7,484

OTHER_LONGTERM_ASSETS_Details

OTHER LONG-TERM ASSETS (Details) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Jun. 30, 2014	Sep. 30, 2013
		Security
OTHER LONG-TERM ASSETS [Abstract]	'	'	'
Auction rate securities	'	$5,895	$7,966
Other long-term assets	'	3,092	3,086
Other long-term investments	'	1,701	1,375
Total	'	10,688	12,427
Number of Auction rate securities	'	2	'
Monetization of Auction Rate Securities	2,113	'	'
Percentage of par value received from auction rate security settlement	65.00%	'	'
Reversal of temporary impairment	234	234	'
Reversal of temporary impairment net of tax	151	'	'
Long-term liability, SERP investments	'	$1,701	'

ACCRUED_EXPENSES_INCOME_TAXES_2

ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES (Details) (USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
ACCRUED EXPENSES, INCOME TAXES PAYABLE AND OTHER CURRENT LIABILITIES [Abstract]	'	'
Accrued compensation	$14,231	$24,601
Goods and services received, not yet invoiced	4,067	4,681
Deferred revenue and customer advances	483	458
Warranty accrual	240	324
Income taxes payable	2,773	7,652
Taxes, other than income taxes	1,164	951
Other	4,507	1,953
Total	$27,465	$40,620

DEBT_Details

DEBT (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2012	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
DEBT [Abstract]	'	'	'	'	'
Debt Instrument, Face Amount	$175,000	'	$175,000	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Debt Instrument, Maturity Date	'	'	27-Jun-19	'	'
Debt issuance costs	550	2,658	550	0	'
Debt issuance costs, current	417	'	417	'	'
Debt issuance costs, noncurrent	1,564	'	1,564	'	'
Line of Credit Facility, Covenant Terms	'	'	'The Credit Agreement contains covenants that restrict the ability of the Company and its subsidiaries to take certain actions, including, among other things and subject to certain significant exceptions: creating liens, incurring indebtedness, making investments, engaging in mergers, selling property, paying dividends or amending organizational documents. The Credit Agreement requires us to comply with certain financial ratio maintenance covenants. As amended, these include a maximum consolidated leverage ratio of 3.00 to 1.00 through December 31, 2015 and a minimum consolidated fixed charge coverage ratio of 1.25 to 1.00. As amended, the maximum consolidated leverage ratio will decrease to 2.75 to 1.00 from January 1, 2016 through the termination of the Credit Agreement. As of June 30, 2014, our consolidated leverage ratio was 1.69 to 1.00 and our consolidated fixed charge coverage ratio was 4.81 to 1.00. The Credit Agreement also contains customary affirmative covenants and events of default. We believe we are in compliance with these covenants.	'	'
Long-term Debt, by Maturity [Abstract]	'	'	'	'	'
Remainder of 2014	2,188	'	2,188	'	'
2015	8,750	'	8,750	'	'
2016	8,750	'	8,750	'	'
2017	7,656	'	7,656	'	'
2018	14,219	'	14,219	'	'
2019	133,437	'	133,437	'	'
Long Term Debt	175,000	'	175,000	'	'
Current portion of long-term debt	8,750	'	8,750	'	10,938
Repayment of long-term debt	'	'	-4,375	-6,563	'
Revolving Credit Facility [Member]	'	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Line of credit facility, borrowing capacity	100,000	'	100,000	'	'
Line of Credit Facility, Additional Borrowing Capacity	100,000	'	100,000	'	'
Line of Credit Facility, Interest Rate Description	'	'	'In addition to paying interest on outstanding principal under the Credit Agreement, we pay a commitment fee to the lenders under the Revolving Credit Facility in respect of the unutilized commitments thereunder. As amended, the fee ranges from 0.20% to 0.30%, based on our consolidated leverage ratio.	'	'
Line of Credit Facility Unused Capacity Commitment Fee Percentage Minimum	'	'	0.20%	'	'
Line of Credit Facility Unused Capacity Commitment Fee Percentage Maximum	'	'	0.30%	'	'
Term Loan [Member]	'	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Line of Credit Facility, Interest Rate Description	'	'	'Borrowings under the amended Credit Facilities (other than in respect of swing-line loans) bear interest at a rate per annum equal to the "Applicable Rate" (as defined below) plus, at our option, either (1) a LIBOR rate determined by reference to the cost of funds for deposits in the relevant currency for the interest period relevant to such borrowing or (2) the "Base Rate", which is the highest of (x) the prime rate of Bank of America, N.A., (y) the federal funds rate plus 1/2 of 1.00% and (z) the one-month LIBOR rate plus 1.00%. The current Applicable Rate for borrowings under the Credit Facilities is 1.50%, as amended, with respect to LIBOR borrowings and 0.25% with respect to Base Rate borrowings, with such Applicable Rate subject to adjustment based on our consolidated leverage ratio. Swing-line loans bear interest at the Base Rate plus the Applicable Rate for Base Rate loans under the Revolving Credit Facility.	'	'
Debt instrument, fair value	$175,000	'	$175,000	'	'

DERIVATIVE_FINANCIAL_INSTRUMEN2

DERIVATIVE FINANCIAL INSTRUMENTS, Schedule of Fair Value of Derivative Instruments in the Consolidated Balance Sheet (Details) (Foreign Exchange Contract [Member], Not Designated as Hedging Instrument [Member], USD $)	Jun. 30, 2014	Sep. 30, 2013
In Thousands, unless otherwise specified
Accrued Expenses and Other Current Liabilities [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair value of foreign exchange contract asset derivatives	$0	$0
Fair value of foreign exchange contract liability derivatives	0	0
Prepaid Expenses and Other Current Assets [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Fair value of foreign exchange contract asset derivatives	172	60
Fair value of foreign exchange contract liability derivatives	$47	$0

DERIVATIVE_FINANCIAL_INSTRUMEN3

DERIVATIVE FINANCIAL INSTRUMENTS, Schedule of the Effect of Derivative Instruments on the Consolidated Statement of Income (Details) (Foreign Exchange Contract [Member], Other Income (Expense), Net [Member], Not Designated as Hedging Instrument [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Foreign Exchange Contract [Member] | Other Income (Expense), Net [Member] | Not Designated as Hedging Instrument [Member]	'	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'	'
Gain (loss) recognized in statement of income	$230	($1)	($107)	$322

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Sep. 30, 2013
Movement in standard product warranty accrual [Roll Forward]	'	'
Balance as of September 30, 2013	$324	'
Reserve for product warranty during the reporting period	555	'
Settlement of warranty	-639	'
Balance as of June 30, 2014	240	324
Purchase obligations [Abstract]	'	'
Contract term	'	'4 years
Contractual commitments for fumed silica and fumed alumina under purchase obligations	$81,742	'

SHAREBASED_COMPENSATION_PLANS_1

SHARE-BASED COMPENSATION PLANS (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
	Director		Director
Omnibus Incentive Plan [Abstract]	'	'	'	'
Share based compensation expense	'	'	$10,897	$10,317
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock based compensation expense	3,106	3,014	10,897	10,317
Stock based compensation - tax benefit	-1,009	-1,010	-3,694	-3,541
Total share-based compensation expense, net of tax	2,097	2,004	7,203	6,776
Number of non-employee directors who have completed two full terms of service	7	'	7	'
Fair value of awards for completing minimum full terms of service	1,325	'	'	'
Cost of Goods Sold [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock based compensation expense	462	385	1,391	1,300
Research, Development and technical [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock based compensation expense	378	313	1,096	989
Selling and Marketing [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock based compensation expense	318	326	978	1,036
General and Administrative [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock based compensation expense	$1,948	$1,990	$7,432	$6,992

OTHER_INCOME_EXPENSE_NET_Detai

OTHER INCOME (EXPENSE), NET (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Other Income (Expense) Net [Line Items]	'	'	'	'
Total other income (expense), net	($132)	$248	$588	$1,565
Interest Income [Member]	'	'	'	'
Other Income (Expense) Net [Line Items]	'	'	'	'
Total other income (expense), net	91	44	170	122
Other Income (Expense) Net [Member]	'	'	'	'
Other Income (Expense) Net [Line Items]	'	'	'	'
Total other income (expense), net	($223)	$204	$418	$1,443

INCOME_TAXES_Details

INCOME TAXES (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income (loss) from continuing operations before income taxes [Abstract]	'	'	'	'
Total	$17,525	$21,555	$46,854	$51,646
Total U.S. and foreign	4,223	5,261	12,149	14,543
Effective income tax rate reconciliation [Abstract]	'	'	'	'
Provision for income taxes (in hundredths)	24.10%	24.40%	25.90%	28.20%
Tax holiday rate percentage	0.00%	'	0.00%	'
Percentage of local statutory rate in effect for 2016 and 2017	50.00%	'	50.00%	'
Income Tax Holiday, Aggregate Dollar Amount	'	'	$2,857	'

EARNINGS_PER_SHARE_Details

EARNINGS PER SHARE (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
EARNINGS PER SHARE [Abstract]	'	'	'	'
Net income	$13,302	$16,294	$34,705	$37,103
Undistributed Earnings Allocated to Participating Securities	-176	-216	-311	-365
Earnings available to common shares	$13,126	$16,078	$34,394	$36,738
Denominator:	'	'	'	'
Weighted average common shares (Denominator for basic calculation, in shares)	23,752,770	22,951,408	23,768,858	22,897,320
Weighted average effect of dilutive securities:	'	'	'	'
Share-based compensation (in shares)	860,722	787,951	935,511	799,909
Diluted weighted average common shares (Denominator for diluted calculation, in shares)	24,613,492	23,739,359	24,704,369	23,697,229
Earnings per share:	'	'	'	'
Basic (in dollars per share)	$0.55	$0.70	$1.45	$1.60
Diluted (in dollars per share)	$0.53	$0.68	$1.39	$1.55
Outstanding stock options excluded from diluted earnings (in shares)	500,000	1,500,000	500,000	1,600,000

FINANCIAL_INFORMATION_BY_INDUS2

FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'
Revenue	$108,358	$109,968	$308,329	$316,865	'
Property, plant and equipment, net	$105,944	'	$105,944	'	$111,985

FINANCIAL_INFORMATION_BY_INDUS3

FINANCIAL INFORMATION BY INDUSTRY SEGMENT, GEOGRAPHIC AREA AND PRODUCT LINE, SEGMENT REPORTING INFORMATION BY PRODUCT TYPE (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	$108,358	$109,968	$308,329	$316,865
Tungsten slurry [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	42,170	38,634	117,098	116,159
Dielectric slurry [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	29,651	30,581	88,718	90,673
Other Metals slurries [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	19,641	20,106	54,782	55,147
Polishing pads [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	8,764	8,451	23,934	24,317
Data storage slurry [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	4,225	5,270	13,693	15,756
Engineered Surface Finishes [Member]	'	'	'	'
Revenue from External Customer [Line Items]	'	'	'	'
Revenue	$3,907	$6,926	$10,104	$14,813