Dispositions - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
Jun. 21, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of businesses		$ 437,875	$ 0	$ 0
Potential contingent proceeds from sale		143,700	0
Gain on sale of assets		288,301	$ 0	$ 0
Non-Core ACC Products [Member] \| Not discontinued operations, disposed of by sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of businesses	$ 263,807
Potential contingent proceeds from sale	480,000	65,700
Gain on sale of assets	$ 288,301	288,300
Disposition related costs		$ 7,900

Disposal Group, Including Discontinued Operation, Assets, Contingent Asset, Noncurrent

No definition available.

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- Definition

Expenses on Disposition of Business

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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