Summary of Significant Accounting Policies - Summarized Financial Data (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Operating expenses	$ 120,972us-gaap_OperatingExpenses	$ 25,726us-gaap_OperatingExpenses
Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Current assets	147,728		63,627
Non-current assets	1,213		1,259
Total assets	148,941		64,886
Current liabilities	14,763		15,346
Non-current liabilities	553		570
Total liabilities	15,316		15,916
Net assets	133,625		48,970
Revenues	636	415
Operating expenses	84,069	12,920
Loss from operations	(83,433)	(12,505)
Other	(1)	81
Net loss	$ (83,434)	$ (12,424)

The amount of assets reported by an equity method investment of the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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The amount of noncurrent assets reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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