Neurocrine Biosciences (NBIX) 10-Q 1 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 25, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'NBIX	'
Entity Registrant Name	'NEUROCRINE BIOSCIENCES INC	'
Entity Central Index Key	'0000914475	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	75,863,034

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$105,532	$44,789
Short-term investments, available for sale	114,330	100,950
Receivables under collaboration agreements and other current assets	1,873	2,723
Total current assets	221,735	148,462
Property and equipment, net	1,798	1,771
Long-term investments, available for sale	51,320	0
Restricted cash	4,443	4,443
Total assets	279,296	154,676
Current liabilities:	'	'
Accounts payable	818	101
Accrued liabilities	6,111	7,955
Current portion of cease-use liability	428	416
Current portion of deferred gain on sale of real estate	3,251	3,227
Total current liabilities	10,608	11,699
Deferred gain on sale of real estate	16,817	17,645
Deferred rent	1,988	1,982
Cease-use liability	2,566	2,680
Other liabilities	260	260
Total liabilities	32,239	34,266
Commitments and contingencies	'	'
Stockholders' equity:	'	'
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.001 par value; 110,000,000 shares authorized; issued and outstanding shares were 75,858,681 as of March 31, 2014 and 67,351,195 as of December 31, 2013	76	67
Additional paid-in capital	1,024,780	886,101
Accumulated other comprehensive (loss) gain	-194	5
Accumulated deficit	-777,605	-765,763
Total stockholders' equity	247,057	120,410
Total liabilities and stockholders' equity	$279,296	$154,676

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]	'	'
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	'	'
Preferred stock, shares outstanding	'	'
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	110,000,000	110,000,000
Common stock, shares issued	75,858,681	67,351,195
Common stock, shares outstanding	75,858,681	67,351,195

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenues:	'	'
License fees	$0	$730
Total revenues	0	730
Operating expenses:	'	'
Research and development	8,572	10,313
General and administrative	4,153	3,392
Total operating expenses	12,725	13,705
Loss from operations	-12,725	-12,975
Other income:	'	'
(Loss) gain on sale/disposal of assets	-10	13
Deferred gain on real estate	804	782
Investment income, net	89	103
Other income, net	0	2
Total other income	883	900
Net loss	-11,842	-12,075
Net loss per common share:	'	'
Basic and diluted	($0.17)	($0.18)
Shares used in the calculation of net loss per common share:	'	'
Basic and diluted	70,260	66,600
Other comprehensive loss:	'	'
Net loss	-11,842	-12,075
Net unrealized losses on available-for-sale securities	-199	-42
Comprehensive loss	($12,041)	($12,117)

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES	'	'
Net loss	($11,842)	($12,075)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:	'	'
Depreciation and amortization	178	175
Gain on sale of assets, net	-794	-795
Deferred revenues	0	-730
Deferred rent	6	38
Amortization of premiums on investments	617	639
Non-cash share-based compensation expense	2,447	1,732
Change in operating assets and liabilities:	'	'
Receivables under collaboration agreements and other assets	850	14,090
Accounts payable and accrued liabilities	-1,127	-968
Cease-use liability	-102	-194
Net cash (used in) provided by operating activities	-9,767	1,912
CASH FLOWS FROM INVESTING ACTIVITIES	'	'
Purchases of investments	-108,907	-66,501
Sales and maturities of investments	43,391	31,470
Proceeds from sales of property and equipment	40	13
Purchases of property and equipment	-255	-59
Net cash used in investing activities	-65,731	-35,077
CASH FLOWS FROM FINANCING ACTIVITIES	'	'
Issuance of common stock	136,241	966
Net cash provided by financing activities	136,241	966
Net increase (decrease) in cash and cash equivalents	60,743	-32,199
Cash and cash equivalents at beginning of the period	44,789	63,754
Cash and cash equivalents at end of the period	$105,532	$31,555

ORGANIZATION_AND_SIGNIFICANT_A

ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES	'
	1. ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES
	Description of Business. Neurocrine Biosciences, Inc. (the Company or Neurocrine) was incorporated in California in 1992 and reincorporated in Delaware in 1996. The Company discovers and develops innovative and life-changing pharmaceuticals, in diseases with high unmet medical needs, through its novel research and development platform, focused on neurological and endocrine based diseases and disorders. The Company’s two lead late-stage clinical programs are elagolix, a gonadotropin-releasing hormone (GnRH) antagonist for women’s health that is partnered with AbbVie Inc. (AbbVie), and a wholly owned vesicular monoamine transporter 2 (VMAT2) inhibitor for the treatment of movement disorders.
	Basis of Presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information and with the instructions of the Securities and Exchange Commission (SEC) on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the condensed consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary.
	These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or for the full year. The balance sheet at December 31, 2013 has been derived from the audited financial statements at that date, but does not include all of the information and footnotes required by GAAP for complete financial statements.
	Use of Estimates. The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and the accompanying notes. Actual results could differ from those estimates.

INVESTMENTS

INVESTMENTS	3 Months Ended
	Mar. 31, 2014
Investments Schedule [Abstract]	'
INVESTMENTS	'
	2. INVESTMENTS
	Available-for-sale securities are carried at fair value, with the unrealized gains and losses reported in comprehensive loss. The amortized cost of debt securities in this category is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization is included in interest income. Realized gains and losses and declines in value judged to be other-than-temporary, if any, on available-for-sale securities are included in other income or expense. The cost of securities sold is based on the specific identification method. Interest and dividends on securities classified as available-for-sale are included in interest income.
	Investments consist of the following (in thousands):
			March 31,		December 31,
			2014		2013
	Certificates of deposit		$	11,217	$	11,012
	Commercial paper			19,964		4,997
	Corporate debt securities			121,940		77,441
	Securities of government sponsored entities			12,529		7,500
	Total investments		$	165,650	$	100,950
	The following is a summary of investments classified as available-for-sale securities (in thousands):
			Contractual		Amortized			Gross		Gross			Aggregate
			Maturity		Cost			Unrealized		Unrealized			Estimated
			(in years)					Gains(1)		Losses(1)			Fair
													Value
	March 31, 2014:
	Classified as current assets:
	Certificates of deposit			Less than 1	$	9,791		$	1	$	(11	)	$	9,781
	Commercial paper			Less than 1		19,968			1		(5	)		19,964
	Corporate debt securities			Less than 1		72,094			8		(46	)		72,056
	Securities of government sponsored entities			Less than 1		12,531			—		(2	)		12,529
	Total short-term available for sale securities				$	114,384		$	10	$	(64	)	$	114,330
	Classified as long-term assets:
	Certificates of deposit			2-Jan		1,440			—		(4	)		1,436
	Corporate debt securities			2-Jan		50,020			—		(136	)		49,884
	Total long-term available for sale securities					51,460			—		(140	)		51,320
	Total available-for-sale securities				$	165,844		$	10	$	(204	)	$	165,650
	December 31, 2013:
	Classified as current assets:
	Certificates of deposit			Less than 1	$	11,018		$	1	$	(7	)	$	11,012
	Commercial paper			Less than 1		4,997			—		—			4,997
	Corporate debt securities			Less than 1		77,430			19		(8	)		77,441
	Securities of government sponsored entities			Less than 1		7,500			—		—			7,500
	Total short-term available for sale securities				$	100,945		$	20	$	(15	)	$	100,950
	-1	Unrealized gains and losses are included in other comprehensive loss.
	The following table presents information about available-for-sale investments in an unrealized loss position (in thousands):
			Less Than 12 Months					12 Months or Greater					Total
			Estimated		Unrealized			Estimated		Unrealized			Estimated		Unrealized
			Fair		Losses			Fair		Losses			Fair		Losses
			Value					Value					Value
	March 31, 2014:
	Certificates of deposit		$	9,296	$	(15	)	$	—	$	—		$	9,296	$	(15	)
	Commercial paper			11,969		(5	)		—		—			11,969		(5	)
	Corporate debt securities			82,745		(182	)		—		—			82,745		(182	)
	Securities of government sponsored entities			5,029		(2	)		—		—			5,029		(2	)
	Total		$	109,039	$	(204	)	$	—	$	—		$	109,039	$	(204	)
	December 31, 2013:
	Certificates of deposit		$	9,802	$	(7	)	$	—	$	—		$	9,802	$	(7	)
	Corporate debt securities			29,919		(8	)		—		—			29,919		(8	)
	Total		$	39,721	$	(15	)	$	—	$	—		$	39,721	$	(15	)

FAIR_VALUE_MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
FAIR VALUE MEASUREMENTS	'
	3. FAIR VALUE MEASUREMENTS
	Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows:
	Level 1:	Observable inputs such as quoted prices in active markets;
	Level 2:	Inputs include quoted prices for similar instruments in active markets and/or quoted prices for identical or similar instruments in markets that are not active near the measurement date; and
	Level 3:	Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.
	The Company classifies its cash equivalents and available for sale investments within Level 1 or Level 2. The fair value of the Company’s high quality investment grade corporate debt securities is determined using proprietary valuation models and analytical tools. These valuation models and analytical tools use market pricing or prices for similar instruments that are both objective and publicly available, including matrix pricing or reported trades, benchmark yields, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids and/or offers. The Company did not reclassify any investments between levels in the fair value hierarchy during the three months ended March 31, 2014.
	The Company’s assets which are measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013 were determined using the inputs described above (in millions):
					Fair Value Measurements Using
		Carrying			Quoted Prices  in			Significant  Other			Significant
		Value			Active			Observable			Unobservable
					Markets for			Inputs			Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	March 31, 2014:
	Classified as current assets:
	Cash and money market funds	$	101.6		$	101.6		$	—		$	—
	Certificates of deposit		9.8			9.8			—			—
	Commercial paper		20			—			20			—
	Securities of government sponsored entities		12.5			—			12.5			—
	Corporate debt securities		76			—			76			—
	Subtotal		219.9			111.4			108.5			—
	Classified as long-term assets:
	Certificates of deposit		5.9			5.9			—			—
	Corporate bonds		49.9			—			49.9			—
	Total		275.7			117.3			158.4			—
	Less cash, cash equivalents and restricted cash		(110.0	)		(106.0	)		(4.0	)		—
	Total investments	$	165.7		$	11.3		$	154.4		$	—
	December 31, 2013:
	Classified as current assets:
	Cash and money market funds	$	34.9		$	34.9		$	—		$	—
	Certificates of deposit		11			11			—			—
	Commercial paper		5			—			5			—
	Securities of government-sponsored entities		7.5			—			7.5			—
	Corporate debt securities		87.4			—			87.4			—
	Subtotal		145.8			45.9			99.9			—
	Classified as long-term assets:
	Certificates of deposit		4.4			4.4			—			—
	Total		150.2			50.3			99.9			—
	Less cash, cash equivalents and restricted cash		(49.2	)		(39.3	)		(9.9	)		—
	Total investments	$	101		$	11		$	90		$	—

SHAREBASED_COMPENSATION

SHARE-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
SHARE-BASED COMPENSATION	'
	4. SHARE-BASED COMPENSATION
	The compensation expense related to the Company’s share-based compensation arrangements has been included in the condensed consolidated statements of comprehensive loss as follows (in millions):
		Three Months Ended
		March 31,
		2014			2013
	General and administrative	$	1.2		$	0.8
	Research and development		1.2			0.9
	Total share-based compensation expense	$	2.4		$	1.7
	The fair value of equity instruments that vest based on continued employee service, net of estimated forfeitures, is recognized and amortized on a straight-line basis over the requisite service period. For restricted stock units (RSUs) with performance-based vesting requirements, no expense is recorded until the performance condition is probable of being achieved. The Company estimates forfeiture rates for equity awards based on past behavior for similar equity awards with further consideration given to the class of employees to whom the equity awards were granted.
	As of March 31, 2014, total unrecognized estimated compensation cost related to non-vested stock options and non-vested RSUs, that vest over a given service period, granted prior to that date was $17.1 million and $9.5 million, respectively, which is expected to be recognized over a weighted average period of approximately 3.0 years and 3.6 years, respectively. Additionally, the Company has approximately 0.5 million RSUs with performance-based vesting requirements outstanding. The total unrecognized estimated compensation cost related to these performance-based RSUs is $9.3 million and is expected to be recognized at the point when the performance conditions have been achieved, which is when these events will become probable
	During the three months ended March 31, 2014 and 2013, stock options to purchase approximately 0.4 million and 0.3 million shares of the Company’s common stock were exercised, respectively. The cash received by the Company from stock option exercises during the three months ended March 31, 2014 and 2013 was approximately $3.0 million and $1.0 million, respectively. The Company also issued approximately 93,000 shares of common stock pursuant to the vesting of RSUs during the three months ended March 31, 2014.
	Stock Options
	The Company granted stock options to purchase approximately 0.8 million and 0.7 million shares of the Company’s common stock during the three months ended March 31, 2014 and 2013, respectively. These stock options all vest monthly over a four-year period. The exercise price of all stock options granted during three months ended March 31, 2014 and 2013 was equal to the closing price of the Company’s common stock on the date of grant. The estimated fair value of each stock option granted was determined on the date of grant using the Black-Scholes option-pricing model with the following weighted-average assumptions for the stock option grants:
		Three Months Ended
		March 31,
		2014		2013
	Risk-free interest rate	2.30%		1.30%
	Expected volatility of common stock	71.30%		75.60%
	Dividend yield	0.00%		0.00%
	Expected option term	7.1 years		7.3 years
	The Black-Scholes option-pricing model incorporates various and highly sensitive assumptions including expected volatility, expected term and interest rates. The expected volatility is based on the historical volatility of the Company’s common stock over the most recent period commensurate with the estimated expected term of the Company’s stock options. The expected option term is estimated based on historical experience as well as the status of the employee. For example, directors and officers have a longer expected option term than all other employees. Additionally, recent grants of stock options have a contractual life of ten years, versus seven years for older option grants, and the vesting period for recent option grants has been extended to four years, which together have also resulted in an increase in the expected option term over time. The risk-free rate for periods within the contractual life of the option is based upon observed interest rates appropriate for the expected term of the Company’s employee stock options. The Company has never declared or paid dividends and has no plans to do so in the foreseeable future. For the three months ended March 31, 2014 and 2013, share-based compensation expense related to stock options was $1.9 million and $1.5 million, respectively.
	Restricted Stock Units
	During the three months ended March 31, 2014, the Company granted approximately 0.4 million RSUs that vest annually over a four year period. Additionally, during the three months ended March 31, 2014, the Company granted approximately 0.5 million RSUs with performance-based vesting requirements (PRSUs) that vest based on the achievement of pre-defined Company-specific performance criteria and expire five years from the grant date. As the performance based criteria for vesting for the PRSUs is not probable, no associated expense has been recorded for the PRSUs during the three months ended March 31, 2014. During the three months ended March 31, 2013, the Company granted approximately 0.4 million RSUs that vest annually over a four year period. The fair value of RSUs is estimated based on the closing sale price of the Company’s common stock on the date of RSU grant. For the three months ended March 31, 2014 and 2013, share-based compensation expense related to RSUs was $0.5 million and $0.2 million, respectively.

STOCKHOLDERS_EQUITY

STOCKHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2014
Equity [Abstract]	'
STOCKHOLDERS' EQUITY	'
	5. STOCKHOLDERS’ EQUITY
	Equity Financing
	In February 2014, the Company completed a public offering of common stock in which the Company sold 8.0 million shares of its common stock at an offering price of $17.75 per share. The net proceeds generated from this transaction, after underwriting discounts and commissions and offering costs were approximately $133.2 million.
	Shelf Registration Statements
	In February 2014, the Company filed an Automatic Shelf Registration statement which immediately became effective by rule of the SEC. For so long as the Company continues to satisfy the requirements to be deemed a well-known seasoned issuer, this shelf registration statement allows the Company to issue an unlimited number of shares of its common stock from time to time. As of March 31, 2014, we had sold 8.0 million shares under this shelf registration statement.
	In December 2012, the SEC declared effective a shelf registration statement filed by the Company in November 2012. The shelf registration statement allows the Company to issue shares of its common stock from time to time for an aggregate initial offering price of up to $150 million.
	The specific terms of future offerings, if any, under any of the shelf registration statements would be established at the time of such offerings.

REAL_ESTATE

REAL ESTATE	3 Months Ended
	Mar. 31, 2014
Leases [Abstract]	'
REAL ESTATE	'
	6. REAL ESTATE
	In December 2007, the Company closed the sale of its facility and associated real property for a purchase price of $109 million. Concurrent with the sale, the Company retired the entire $47.7 million in mortgage debt previously outstanding with respect to the facility and associated real property, and received cash of $61.0 million net of transaction costs and debt retirement.
	Upon the closing of the sale of the facility and associated real property, the Company entered into a lease agreement (Lease) with DMH Campus Investors, LLC (DMH) whereby it leased back for an initial term of 12 years its corporate headquarters comprised of two buildings located at 12790 El Camino Real (Front Building) and 12780 El Camino Real (Rear Building) in San Diego, California. The Company also entered into a series of lease amendments (Amendments), beginning in late 2008, through which it vacated the Front Building, but continues to occupy the Rear Building. The ultimate result of this real estate sale was a net gain of $39.1 million which was deferred in accordance with authoritative guidance. The Company recognized $0.8 million of the deferred gain during each of the three month periods ended March 31, 2014 and 2013, and will recognize the remaining $20.1 million of the deferred gain over the initial Lease term which will expire at the end of 2019.
	Under the terms of the Lease and the Amendments, the Company pays base annual rent (subject to an annual fixed percentage increase), plus a 3.5% annual management fee, property taxes and other normal and necessary expenses associated with the Lease such as utilities, repairs and maintenance. In lieu of a cash security deposit under the Lease, Wells Fargo Bank, N.A. issued on the Company’s behalf a letter of credit in the amount of $4.2 million, which is secured by a deposit of equal amount with the same bank. The Company also has the right to extend the Lease for two consecutive ten-year terms.
	In December 2010, the Company entered into a sublease agreement (Sublease) for approximately 16,000 square feet of the Rear Building. The Sublease is expected to result in approximately $0.6 million of rental income per year over the three year initial term of the Sublease and is recorded as an offset to rent expense. The Sublease provides an option to extend for two one-year renewal periods. The income generated under the Sublease is lower than the Company’s financial obligation under the Lease for the Rear Building with DMH, as determined on a per square foot basis. Consequently, at December 31, 2010 the Company was required to record a cease-use liability for the net present value estimated difference between the expected income to be generated under the Sublease and future subleases and the Lease obligation over the remaining term of the Lease for the space that is occupied by the subtenant. This transaction resulted in $2.5 million of gross cease-use expense, and a reversal of $173,000 in associated deferred rent, each being recorded in December 2010. In August 2012, the Company extended the terms of the Sublease and increased the leased square footage to approximately 17,000 square feet. This transaction resulted in approximately $150,000 of gross cease-use expense, and a reversal of $15,000 in associated deferred rent, each being recorded in September 2012.
	In September 2011, the Company entered into a second sublease agreement (Second Sublease) for approximately 3,300 square feet of space in the Rear Building. The Second Sublease is expected to result in approximately $0.1 million in rental income per year over the three year term and is recorded as an offset to rent expense. The Second Sublease provides an option to extend for a one-year renewal period. Similar to the Sublease, the Second Sublease resulted in $0.3 million of gross cease-use expense, and a reversal of $47,000 in associated deferred rent, each being recorded in September 2011.
	In November 2012, the Company entered into a third sublease agreement (Third Sublease) for approximately 14,000 square feet of space in the Rear Building. The Third Sublease is expected to result in approximately $0.5 million in rental income per year over the three and a half year term and is recorded as an offset to rent expense. The Third Sublease provides the subtenant with an option to extend the term for two one-year renewal periods. Similar to the previous subleases, the Third Sublease resulted in $1.2 million of gross cease-use expense, and a reversal of $250,000 in associated deferred rent, each being recorded in December 2012.
	The following table sets forth changes to the accrued cease-use liability during the three months ended March 31, 2014 and 2013 (in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Beginning balance	$	3,096		$	3,686
	Payments		(102	)		(194	)
	Ending balance	$	2,994		$	3,492

LOSS_PER_COMMON_SHARE

LOSS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
LOSS PER COMMON SHARE	'
	7. LOSS PER COMMON SHARE
	The Company computes basic net loss per share using the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing the net loss for the period by the weighted average number of common and common equivalent shares outstanding during the period. Additionally, potentially dilutive securities, composed of incremental common shares issuable upon the exercise of stock options and warrants and the vesting of RSUs, are excluded from the diluted loss per share calculation because of their anti-dilutive effect.
	For the three months ended March 31, 2014, the Company realized a net loss of $11.8 million. Potentially dilutive securities totaled approximately 3.0 million for the three months ended March 31, 2014. Options to purchase approximately 0.9 million shares of common stock were outstanding during the three months ended March 31, 2014 with an exercise price greater than the average market price of the underlying common shares.
	For the three months ended March 31, 2013, the Company realized a net loss of $12.1 million. Potentially dilutive securities totaled approximately 2.0 million for the three months ended March 31, 2013. Options to purchase approximately 0.8 million shares of common stock were outstanding during the three months ended March 31, 2013 with an exercise price greater than the average market price of the underlying common shares.

RESEARCH_AND_DEVELOPMENT

RESEARCH AND DEVELOPMENT	3 Months Ended
	Mar. 31, 2014
Research And Development [Abstract]	'
RESEARCH AND DEVELOPMENT	'
	8. RESEARCH AND DEVELOPMENT
	Research and development (R&D) expenses consists primarily of salaries, payroll taxes, employee benefits, and share-based compensation charges, for those individuals involved in ongoing R&D efforts; as well as scientific contractor fees, preclinical and clinical trial costs, R&D facilities costs, laboratory supply costs, and depreciation of scientific equipment. All such costs are charged to R&D expense as incurred. These expenses result from the Company’s independent R&D efforts as well as efforts associated with collaborations and in-licensing arrangements. In addition, the Company funds R&D at other companies and research institutions under agreements, which are generally cancelable. The Company reviews and accrues clinical trial expenses based on work performed, which relies on estimates of total costs incurred based on patient enrollment, completion of patient studies and other events. The Company follows this method since reasonably dependable estimates of the costs applicable to various stages of a research agreement or clinical trial can be made. Accrued clinical costs are subject to revisions as trials progress. Revisions are charged to expense in the period in which the facts that give rise to the revision become known.

ORGANIZATION_AND_SIGNIFICANT_A1

ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information and with the instructions of the Securities and Exchange Commission (SEC) on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the condensed consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiary.
	These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or for the full year. The balance sheet at December 31, 2013 has been derived from the audited financial statements at that date, but does not include all of the information and footnotes required by GAAP for complete financial statements.
Use of Estimates	'
	Use of Estimates. The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and the accompanying notes. Actual results could differ from those estimates.

INVESTMENTS_Tables

INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2014
Investments Schedule [Abstract]	'
Investments	'
	Investments consist of the following (in thousands):
			March 31,		December 31,
			2014		2013
	Certificates of deposit		$	11,217	$	11,012
	Commercial paper			19,964		4,997
	Corporate debt securities			121,940		77,441
	Securities of government sponsored entities			12,529		7,500
	Total investments		$	165,650	$	100,950
Summary of Investments Classified as Available-For-Sale Securities	'
	The following is a summary of investments classified as available-for-sale securities (in thousands):
			Contractual		Amortized			Gross		Gross			Aggregate
			Maturity		Cost			Unrealized		Unrealized			Estimated
			(in years)					Gains(1)		Losses(1)			Fair
													Value
	March 31, 2014:
	Classified as current assets:
	Certificates of deposit			Less than 1	$	9,791		$	1	$	(11	)	$	9,781
	Commercial paper			Less than 1		19,968			1		(5	)		19,964
	Corporate debt securities			Less than 1		72,094			8		(46	)		72,056
	Securities of government sponsored entities			Less than 1		12,531			—		(2	)		12,529
	Total short-term available for sale securities				$	114,384		$	10	$	(64	)	$	114,330
	Classified as long-term assets:
	Certificates of deposit			2-Jan		1,440			—		(4	)		1,436
	Corporate debt securities			2-Jan		50,020			—		(136	)		49,884
	Total long-term available for sale securities					51,460			—		(140	)		51,320
	Total available-for-sale securities				$	165,844		$	10	$	(204	)	$	165,650
	December 31, 2013:
	Classified as current assets:
	Certificates of deposit			Less than 1	$	11,018		$	1	$	(7	)	$	11,012
	Commercial paper			Less than 1		4,997			—		—			4,997
	Corporate debt securities			Less than 1		77,430			19		(8	)		77,441
	Securities of government sponsored entities			Less than 1		7,500			—		—			7,500
	Total short-term available for sale securities				$	100,945		$	20	$	(15	)	$	100,950
	-1	Unrealized gains and losses are included in other comprehensive loss.
Available-For-Sale Investments in Unrealized Loss Position	'
	The following table presents information about available-for-sale investments in an unrealized loss position (in thousands):
			Less Than 12 Months					12 Months or Greater					Total
			Estimated		Unrealized			Estimated		Unrealized			Estimated		Unrealized
			Fair		Losses			Fair		Losses			Fair		Losses
			Value					Value					Value
	March 31, 2014:
	Certificates of deposit		$	9,296	$	(15	)	$	—	$	—		$	9,296	$	(15	)
	Commercial paper			11,969		(5	)		—		—			11,969		(5	)
	Corporate debt securities			82,745		(182	)		—		—			82,745		(182	)
	Securities of government sponsored entities			5,029		(2	)		—		—			5,029		(2	)
	Total		$	109,039	$	(204	)	$	—	$	—		$	109,039	$	(204	)
	December 31, 2013:
	Certificates of deposit		$	9,802	$	(7	)	$	—	$	—		$	9,802	$	(7	)
	Corporate debt securities			29,919		(8	)		—		—			29,919		(8	)
	Total		$	39,721	$	(15	)	$	—	$	—		$	39,721	$	(15	)

FAIR_VALUE_MEASUREMENTS_Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Assets Measured at Fair Value on Recurring Basis	'
	The Company’s assets which are measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013 were determined using the inputs described above (in millions):
					Fair Value Measurements Using
		Carrying			Quoted Prices  in			Significant  Other			Significant
		Value			Active			Observable			Unobservable
					Markets for			Inputs			Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	March 31, 2014:
	Classified as current assets:
	Cash and money market funds	$	101.6		$	101.6		$	—		$	—
	Certificates of deposit		9.8			9.8			—			—
	Commercial paper		20			—			20			—
	Securities of government sponsored entities		12.5			—			12.5			—
	Corporate debt securities		76			—			76			—
	Subtotal		219.9			111.4			108.5			—
	Classified as long-term assets:
	Certificates of deposit		5.9			5.9			—			—
	Corporate bonds		49.9			—			49.9			—
	Total		275.7			117.3			158.4			—
	Less cash, cash equivalents and restricted cash		(110.0	)		(106.0	)		(4.0	)		—
	Total investments	$	165.7		$	11.3		$	154.4		$	—
	December 31, 2013:
	Classified as current assets:
	Cash and money market funds	$	34.9		$	34.9		$	—		$	—
	Certificates of deposit		11			11			—			—
	Commercial paper		5			—			5			—
	Securities of government-sponsored entities		7.5			—			7.5			—
	Corporate debt securities		87.4			—			87.4			—
	Subtotal		145.8			45.9			99.9			—
	Classified as long-term assets:
	Certificates of deposit		4.4			4.4			—			—
	Total		150.2			50.3			99.9			—
	Less cash, cash equivalents and restricted cash		(49.2	)		(39.3	)		(9.9	)		—
	Total investments	$	101		$	11		$	90		$	—

SHAREBASED_COMPENSATION_Tables

SHARE-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Compensation Expenses Related to Share Based Compensation	'
	The compensation expense related to the Company’s share-based compensation arrangements has been included in the condensed consolidated statements of comprehensive loss as follows (in millions):
		Three Months Ended
		March 31,
		2014			2013
	General and administrative	$	1.2		$	0.8
	Research and development		1.2			0.9
	Total share-based compensation expense	$	2.4		$	1.7
Weighted-Average Assumptions for Stock Option Grants using Black-Scholes Option-Pricing Model	'
	The estimated fair value of each stock option granted was determined on the date of grant using the Black-Scholes option-pricing model with the following weighted-average assumptions for the stock option grants:
		Three Months Ended
		March 31,
		2014		2013
	Risk-free interest rate	2.30%		1.30%
	Expected volatility of common stock	71.30%		75.60%
	Dividend yield	0.00%		0.00%
	Expected option term	7.1 years		7.3 years

REAL_ESTATE_Tables

REAL ESTATE (Tables)	3 Months Ended
	Mar. 31, 2014
Leases [Abstract]	'
Changes to Accrued Cease-Use Liability	'
	The following table sets forth changes to the accrued cease-use liability during the three months ended March 31, 2014 and 2013 (in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Beginning balance	$	3,096		$	3,686
	Payments		(102	)		(194	)
	Ending balance	$	2,994		$	3,492

Investments_Detail

Investments (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Investments [Line Items]	'	'
Investments	$165,650	$100,950
Certificates of deposit	'	'
Schedule of Investments [Line Items]	'	'
Investments	11,217	11,012
Commercial paper	'	'
Schedule of Investments [Line Items]	'	'
Investments	19,964	4,997
Corporate debt securities	'	'
Schedule of Investments [Line Items]	'	'
Investments	121,940	77,441
Securities of government-sponsored entities	'	'
Schedule of Investments [Line Items]	'	'
Investments	$12,529	$7,500

Summary_of_Investments_Classif

Summary of Investments Classified as Available-For-Sale Securities (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized Cost	$165,844		'
Gross Unrealized Gains	10	[1]	'
Gross Unrealized Losses	-204	[1]	'
Aggregate Estimated Fair Value	165,650		100,950
Certificates of deposit	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Aggregate Estimated Fair Value	11,217		11,012
Commercial paper	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Aggregate Estimated Fair Value	19,964		4,997
Corporate debt securities	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Aggregate Estimated Fair Value	121,940		77,441
Securities of government-sponsored entities	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Aggregate Estimated Fair Value	12,529		7,500
Short-term investments	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized Cost	114,384		100,945
Gross Unrealized Gains	10	[1]	20	[1]
Gross Unrealized Losses	-64	[1]	-15	[1]
Aggregate Estimated Fair Value	114,330		100,950
Short-term investments | Certificates of deposit	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'1 year
Amortized Cost	9,791		11,018
Gross Unrealized Gains	1	[1]	1	[1]
Gross Unrealized Losses	-11	[1]	-7	[1]
Aggregate Estimated Fair Value	9,781		11,012
Short-term investments | Commercial paper	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'1 year
Amortized Cost	19,968		4,997
Gross Unrealized Gains	1	[1]	0	[1]
Gross Unrealized Losses	-5	[1]	0	[1]
Aggregate Estimated Fair Value	19,964		4,997
Short-term investments | Corporate debt securities	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'1 year
Amortized Cost	72,094		77,430
Gross Unrealized Gains	8	[1]	19	[1]
Gross Unrealized Losses	-46	[1]	-8	[1]
Aggregate Estimated Fair Value	72,056		77,441
Short-term investments | Securities of government-sponsored entities	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'1 year
Amortized Cost	12,531		7,500
Gross Unrealized Gains	0	[1]	0	[1]
Gross Unrealized Losses	-2	[1]	0	[1]
Aggregate Estimated Fair Value	12,529		7,500
Long-term investments	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized Cost	51,460		'
Gross Unrealized Gains	0	[1]	'
Gross Unrealized Losses	-140	[1]	'
Aggregate Estimated Fair Value	51,320		'
Long-term investments | Certificates of deposit	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized Cost	1,440		'
Gross Unrealized Gains	0	[1]	'
Gross Unrealized Losses	-4	[1]	'
Aggregate Estimated Fair Value	1,436		'
Long-term investments | Certificates of deposit | Minimum	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'
Long-term investments | Certificates of deposit | Maximum	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'2 years		'
Long-term investments | Corporate debt securities	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Amortized Cost	50,020		'
Gross Unrealized Gains	0	[1]	'
Gross Unrealized Losses	-136	[1]	'
Aggregate Estimated Fair Value	$49,884		'
Long-term investments | Corporate debt securities | Minimum	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'1 year		'
Long-term investments | Corporate debt securities | Maximum	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Available for sale securities contractual maturity	'2 years		'
[1]	Unrealized gains and losses are included in other comprehensive loss.

AvailableForSale_Investments_i

Available-For-Sale Investments in Unrealized Loss Position (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Less Than 12 Months, Estimated Fair Value	$109,039	$39,721
Less Than 12 Months, Unrealized Losses	-204	-15
12 Months or Greater, Estimated Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total Estimated Fair Value	109,039	39,721
Total Unrealized Losses	-204	-15
Certificates of deposit	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less Than 12 Months, Estimated Fair Value	9,296	9,802
Less Than 12 Months, Unrealized Losses	-15	-7
12 Months or Greater, Estimated Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total Estimated Fair Value	9,296	9,802
Total Unrealized Losses	-15	-7
Commercial paper	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less Than 12 Months, Estimated Fair Value	11,969	'
Less Than 12 Months, Unrealized Losses	-5	'
12 Months or Greater, Estimated Fair Value	0	'
12 Months or Greater, Unrealized Losses	0	'
Total Estimated Fair Value	11,969	'
Total Unrealized Losses	-5	'
Corporate debt securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less Than 12 Months, Estimated Fair Value	82,745	29,919
Less Than 12 Months, Unrealized Losses	-182	-8
12 Months or Greater, Estimated Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total Estimated Fair Value	82,745	29,919
Total Unrealized Losses	-182	-8
Securities of government-sponsored entities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Less Than 12 Months, Estimated Fair Value	5,029	'
Less Than 12 Months, Unrealized Losses	-2	'
12 Months or Greater, Estimated Fair Value	0	'
12 Months or Greater, Unrealized Losses	0	'
Total Estimated Fair Value	5,029	'
Total Unrealized Losses	($2)	'

Assets_Measured_at_Fair_Value_

Assets Measured at Fair Value on Recurring Basis (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	$165.70	$101
Investments Including Cash Equivalents And Restricted Cash	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	275.7	150.2
Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	110	49.2
Short-term investments	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	219.9	145.8
Short-term investments | Cash and money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	101.6	34.9
Short-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	9.8	11
Short-term investments | Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	20	5
Short-term investments | Securities of government-sponsored entities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	12.5	7.5
Short-term investments | Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	76	87.4
Long-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	5.9	4.4
Long-term investments | Corporate bonds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Carrying Value	49.9	'
Quoted Prices in Active Markets for Identical Assets (Level 1)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	11.3	11
Quoted Prices in Active Markets for Identical Assets (Level 1) | Investments Including Cash Equivalents And Restricted Cash	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	117.3	50.3
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	106	39.3
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	111.4	45.9
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Cash and money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	101.6	34.9
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	9.8	11
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Securities of government-sponsored entities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Short-term investments | Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Long-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	5.9	4.4
Quoted Prices in Active Markets for Identical Assets (Level 1) | Long-term investments | Corporate bonds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	'
Significant Other Observable Inputs (Level 2)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	154.4	90
Significant Other Observable Inputs (Level 2) | Investments Including Cash Equivalents And Restricted Cash	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	158.4	99.9
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	4	9.9
Significant Other Observable Inputs (Level 2) | Short-term investments	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	108.5	99.9
Significant Other Observable Inputs (Level 2) | Short-term investments | Cash and money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Other Observable Inputs (Level 2) | Short-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Other Observable Inputs (Level 2) | Short-term investments | Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	20	5
Significant Other Observable Inputs (Level 2) | Short-term investments | Securities of government-sponsored entities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	12.5	7.5
Significant Other Observable Inputs (Level 2) | Short-term investments | Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	76	87.4
Significant Other Observable Inputs (Level 2) | Long-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Other Observable Inputs (Level 2) | Long-term investments | Corporate bonds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	49.9	'
Significant Unobservable Inputs (Level 3)	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Investments Including Cash Equivalents And Restricted Cash	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Cash and Cash Equivalents	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments | Cash and money market funds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments | Commercial paper	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments | Securities of government-sponsored entities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Short-term investments | Corporate debt securities	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Long-term investments | Certificates of deposit	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	0	0
Significant Unobservable Inputs (Level 3) | Long-term investments | Corporate bonds	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair value of assets on recurring basis	$0	'

Compensation_Expense_Related_t

Compensation Expense Related to Share-Based Compensation (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total share-based compensation expense	$2.40	$1.70
General and Administrative Expense	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total share-based compensation expense	1.2	0.8
Research and Development Expense	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total share-based compensation expense	$1.20	$0.90

ShareBased_Compensation_Additi

Share-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock option exercised	400,000	300,000
Cash received from stock option exercises	$3	$1
Common stock issued pursuant to the vesting of restricted stock units (RSUs)	93,000	'
Stock options granted	800,000	700,000
Stock vesting period	'4 years	'
Stock option contractual life	'10 years	'
Share-based compensation expense	2.4	1.7
Due to Changes in the Plan | Scenario, Previously Reported	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock option contractual life	'7 years	'
Restricted Stock Units (RSUs)	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Unrecognized compensation cost	9.5	'
Unrecognized compensation cost, weighted average period of recognition	'3 years 7 months 6 days	'
Stock vesting period	'4 years	'4 years
Share-based compensation expense	0.5	0.2
Restricted stock units granted	400,000	400,000
Stock Options	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Unrecognized compensation cost	17.1	'
Unrecognized compensation cost, weighted average period of recognition	'3 years	'
Stock vesting period	'4 years	'
Share-based compensation expense	1.9	1.5
Performance-based RSUs	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Unrecognized compensation cost	9.3	'
RSU with performance-based vesting requirements outstanding	500,000	'
Stock vesting period	'5 years	'
Share-based compensation expense	$0	'
Restricted stock units granted	500,000	'

WeightedAverage_Assumptions_fo

Weighted-Average Assumptions for Stock Option Grants using Black-Scholes Option-Pricing Model (Detail) (Stock Options)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Stock Options	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Risk-free interest rate	2.30%	1.30%
Expected volatility of common stock	71.30%	75.60%
Dividend yield	0.00%	0.00%
Expected option term	'7 years 1 month 6 days	'7 years 3 months 18 days

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		0 Months Ended
Share data in Millions, except Per Share data, unless otherwise specified	Feb. 28, 2014	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2012
				Shelf Registration	Shelf Registration
					Maximum
Class of Stock [Line Items]	'	'	'	'	'
Common stock issued	8	'	'	8	'
Common stock, offering price	$17.75	'	'	'	'
Proceeds from common stock issuance	$133,200,000	$136,241,000	$966,000	'	'
Aggregate initial offering price of common stock	'	'	'	'	$150,000,000

Real_Estate_Additional_Informa

Real Estate - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended			1 Months Ended
	Dec. 31, 2007	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2008	Sep. 30, 2012	Aug. 31, 2012	Dec. 31, 2010	Sep. 30, 2011	Dec. 31, 2012	Nov. 30, 2012
	Building	RenewalOptions			Sublease	Sublease	Sublease	Second Sublease	Third Sublease	Third Sublease
						sqft	sqft	sqft		sqft
Real Estate Properties [Line Items]	'	'	'	'	'	'	'	'	'	'
Sale of facility and associated real property	$109,000,000	'	'	'	'	'	'	'	'	'
Mortgage debt retired	47,700,000	'	'	'	'	'	'	'	'	'
Cash received net of transaction costs and debt retirement	61,000,000	'	'	'	'	'	'	'	'	'
Leaseback transaction lease period	'12 years	'	'	'	'	'	'	'	'	'
Number of building leased	2	'	'	'	'	'	'	'	'	'
Net deferred gain on real estate sale	'	20,100,000	'	39,100,000	'	'	'	'	'	'
Deferred gain recognized on real estate sale	'	800,000	800,000	'	'	'	'	'	'	'
Lease expiration year	'	'	'2019	'	'	'	'	'	'	'
Percentage of management fee included in the base annual rent	'	3.50%	'	'	'	'	'	'	'	'
Letter of credit	'	4,200,000	'	'	'	'	'	'	'	'
Lease extension period	'	'10 years	'	'	'	'	'	'	'	'
Number of times to renew the lease contract	'	2	'	'	'	'	'	'	'	'
Subleased area	'	'	'	'	'	17,000	16,000	3,300	'	14,000
Rental income from sublease agreement	'	'	'	'	'	'	600,000	100,000	'	500,000
Sublease agreement period	'	'	'	'	'	'	'3 years	'3 years	'	'3 years 6 months
Lease renewal additional periods	'	'	'	'	'	'	'1 year	'1 year	'	'1 year
Cease-use expense	'	'	'	'	'	150,000	2,500,000	300,000	'	1,200,000
Deferred rent reversed	'	'	'	'	$15,000	'	$173,000	$47,000	$250,000	'

Changes_to_Accrued_CeaseUse_Li

Changes to Accrued Cease-Use Liability (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'	'
Beginning balance	$3,096	$3,686
Payments	-102	-194
Ending balance	$2,994	$3,492

Loss_Per_Common_Share_Addition

Loss Per Common Share - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, except Share data in Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]	'	'
Net (loss) income	($11,842)	($12,075)
Potentially dilutive securities	3	2
Shares of common stock excluded from computation of diluted earnings per share outstanding	0.9	0.8