Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

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No definition available.

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Name of the acquired entity.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Acquisitions and Divestitures (Details 1) - USD ($)			3 Months Ended		9 Months Ended		12 Months Ended
Acquisitions and Divestitures (Details 1) - USD ($)	Sep. 04, 2018	Apr. 06, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Proceeds from Divestiture of Businesses					$ 4,000,000	$ 0
Gain on Sale of Business					1,000,000
Purchase accounting adjustments					4,627,000
Amortization of Intangible Assets			$ 5,720,000	$ 7,650,000	$ 17,378,000	$ 11,430,000
Trade Names
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					10 years		10 years
Customer Lists
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					15 years		15 years
Technology
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					11 years		11 years
Senior Secured Credit Facility
Business Acquisition [Line Items]
Long-term Line of Credit, Noncurrent		$ 420,000,000
IP Cleaning S.p.A
Business Acquisition [Line Items]
Business Acquisition, Name of Acquired Entity		IP Cleaning S.p.A. and its subsidiaries ("IPC Group")
Business Combination, Consideration Transferred		$ 353,769,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Cash Equivalents		8,804,000
Business Acquisition, Goodwill, Expected Tax Deductible Amount		$ 0
Purchase accounting adjustments					$ 4,627,000
Amortization of Intangible Assets			$ 5,401,000		$ 16,424,000
IP Cleaning S.p.A \| Trade Names
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
IP Cleaning S.p.A \| Customer Lists
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		15 years
IP Cleaning S.p.A \| Technology
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Gaomei
Business Acquisition [Line Items]
Business Acquisition, Name of Acquired Entity	Hefei Gaomei Cleaning Machines Co., Ltd. and Anhui Rongen Environmental Protection Technology Co., Ltd (collectively "Gaomei")