The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

The number of positions eliminated as of the balance sheet date since inception of the restructuring plan(s).

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Percentage of the total number of positions eliminated as of the balance sheet date since inception of the restructuring plan(s).

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Restructuring (Details)	12 Months Ended
Restructuring (Details)	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2014 position
Restructuring
Number of full time employee positions eliminated \| position				80
Percentage of full time employee positions eliminated				30.00%
Restructuring charge	$ 100,000
Restructuring reserve	0		$ 0
Asset retirement obligation	$ 200,000
Cost of product sales
Restructuring
Restructuring charge		$ 2,500,000
Selling, general and administrative expenses
Restructuring
Restructuring charge		500,000
CTRM Business
Restructuring
Restructuring charge		$ 3,000,000