Income Taxes (Schedule Of Differences Between Statutory Tax And Effective Tax) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes Schedule Of Differences Between Statutory Tax And Effective Tax Details
Computed "expected" tax benefit	$ (2,699)	$ (4,529)	$ (6,370)
IRC §382 adjustment	0npsp_Irc382Adjustment	6,575npsp_Irc382Adjustment	59,822npsp_Irc382Adjustment
Change in the valuation allowance for deferred tax assets attributable to operations and other adjustments	(7,158)	2,840	(42,124)
Research credit	(9,217)	(12,237)	(10,231)
State income taxes, net of federal tax effect	527	182	0
Equity based compensation expense	1,310	678	513
Intercompany license of intellectual property	0	5,440	0
Foreign tax rate differences	15,358	940	0
Non recourse debt	2,056	(78)	(1,663)
Other	589	371	53
Income tax expense (benefit)	$ 766us-gaap_IncomeTaxExpenseBenefit	$ 182us-gaap_IncomeTaxExpenseBenefit	$ 0us-gaap_IncomeTaxExpenseBenefit

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to differences caused by IRC section 382 provisions.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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