Gross-to-Net Product Sales - Reconciliation of Gross-to-Net Product Sales (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenue, Net [Abstract]
Gross product sales	$ 62,598us-gaap_SalesRevenueGoodsGross	$ 61,500us-gaap_SalesRevenueGoodsGross
Rebates and chargebacks	(18,144)sppi_RebatesAndChargeBacks	(16,949)sppi_RebatesAndChargeBacks
Data, distribution and GPO administrative fees	(5,571)sppi_DataDistributionAndGpoFees	(4,497)sppi_DataDistributionAndGpoFees
Prompt pay discount	0us-gaap_SalesDiscountsGoods	(2)us-gaap_SalesDiscountsGoods
Product returns allowance	(470)us-gaap_SalesReturnsAndAllowancesGoods	44us-gaap_SalesReturnsAndAllowancesGoods
Product sales, net	$ 38,413us-gaap_SalesRevenueGoodsNet	$ 40,096us-gaap_SalesRevenueGoodsNet

Data Distribution and GPO Fees

No definition available.

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- Definition

Rebates And Charge backs

+ References

No definition available.

+ Details

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- Definition

Aggregate cash discounts given by the entity for goods sold to customers including, but not limited to, early payments of accounts due. For example, selling terms of "2/10, net 30" entitle a customer to a 2% discount for prompt payment within 10 days, otherwise full payment is expected in 30 days. Discounts are a deduction from gross revenue in arriving at net revenue.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(a))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Definition

Total deduction from sales during the period arising from goods returned by customers (other than under warranty provisions) and price reductions (allowance, price protection agreements) given by the entity. Returns and allowances are a deduction from gross revenue in arriving at net revenue.

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+ Details

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- Definition

Aggregate revenue during the period from sale of goods in the normal course of business, before deducting returns, allowances and discounts.

+ References

+ Details

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

+ Details

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