Commitments and Contingencies - Insurance Proceeds Receivable and Provision of Legal Settlements (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Class action lawsuit insurance proceeds	$ 0	$ 22,000
Provision for Legal Settlements	(39,612)	(64,010)
Less: Provision for legal settlements - current	(8,596)	(64,010)
Provision for legal settlements - non-current	(31,016)	0
Class action lawsuit settlement
Business Acquisition [Line Items]
Provision for Legal Settlements	0	(22,250)
DOJ and SEC settlement
Business Acquisition [Line Items]
Provision for Legal Settlements	(39,612)	(40,635)
Relator legal settlement
Business Acquisition [Line Items]
Provision for Legal Settlements	0	(620)
Relators legal fees
Business Acquisition [Line Items]
Provision for Legal Settlements	0	(405)
Other litigation settlement
Business Acquisition [Line Items]
Provision for Legal Settlements	$ 0	$ (100)

Loss Contingency, Settlement Liability, Current

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- Definition

Loss Contingency, Settlement Liability, Noncurrent

+ 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

Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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