Nuvasive (NUVA) 10-Q 26 Apr 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 21, 2016
Document And Entity Information [Abstract]
Entity Registrant Name	NUVASIVE INC
Entity Central Index Key	1,142,596
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Trading Symbol	NUVA
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		49,833,030

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 270,105	$ 192,339
Short-term marketable securities	42,495	165,423
Accounts receivable, net of allowances of $5,856 and $5,320, respectively	126,088	127,595
Inventory, net	200,711	168,140
Prepaid income taxes	44,921	40,540
Prepaid expenses and other current assets	7,844	8,790
Total current assets	692,164	702,827
Property and equipment, net	152,988	141,441
Long-term marketable securities	18,381	112,332
Intangible assets, net	266,089	85,076
Goodwill	404,307	154,281
Deferred tax assets	8,176	67,051
Restricted cash and investments	7,316	5,615
Other assets	19,698	17,404
Total assets	1,569,119	1,286,027
Current liabilities:
Accounts payable and accrued liabilities	77,357	60,986
Accrued payroll and related expenses	30,276	37,641
Contingent liabilities	19,497
Income tax liabilities	930	990
Total current liabilities	128,060	99,617
Senior convertible notes	669,398	372,920
Deferred and income tax liabilities, non-current	11,496	8,602
Non-current litigation liabilities	88,310	88,261
Other long-term liabilities	$ 20,170	$ 14,425
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized, none outstanding
Common stock, $0.001 par value; 120,000,000 shares authorized at March 31, 2016 and December 31, 2015, 53,418,900 and 52,616,471 issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 53	$ 53
Additional paid-in capital	961,206	989,387
Accumulated other comprehensive loss	(9,079)	(12,112)
Accumulated deficit	(129,533)	(120,647)
Treasury stock at cost; 3,647,690 shares and 3,316,794 shares at March 31, 2016 and December 31, 2015, respectively	(177,814)	(161,788)
Total NuVasive, Inc. stockholders’ equity	644,833	694,893
Non-controlling interests	6,852	7,309
Total equity	651,685	702,202
Total liabilities and equity	$ 1,569,119	$ 1,286,027

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 5,856	$ 5,320
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	53,418,900	52,616,471
Common stock, shares outstanding	53,418,900	52,616,471
Treasury stock at cost, shares	3,647,690	3,316,794

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Revenue	$ 215,104,000	$ 192,383,000
Cost of goods sold (excluding below amortization of intangible assets)	54,226,000	45,664,000
Gross profit	160,878,000	146,719,000
Operating expenses:
Sales, marketing and administrative	130,195,000	116,096,000
Research and development	10,629,000	9,264,000
Amortization of intangible assets	7,871,000	2,996,000
Litigation liability (gain)	0	(42,575,000)
Business transition costs	(50,000)	5,373,000
Total operating expenses	148,645,000	91,154,000
Interest and other expense, net:
Interest income	328,000	419,000
Interest expense	(8,472,000)	(7,126,000)
Loss on repurchases of convertible notes	(17,444,000)
Other income, net	50,000	424,000
Total interest and other expense, net	(25,538,000)	(6,283,000)
(Loss) income before income taxes	(13,305,000)	49,282,000
Income tax benefit (expense)	3,962,000	(17,885,000)
Consolidated net (loss) income	(9,343,000)	31,397,000
Add back net loss attributable to non-controlling interests	(457,000)	(163,000)
Net (loss) income attributable to NuVasive, Inc.	$ (8,886,000)	$ 31,560,000
Net (loss) income per share attributable to NuVasive, Inc.:
Basic	$ (0.18)	$ 0.66
Diluted	$ (0.18)	$ 0.61
Weighted average shares outstanding:
Basic	49,617	47,989
Diluted	49,617	51,716

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net (loss) income	$ (9,343)	$ 31,397
Other comprehensive income (loss):
Unrealized gain on marketable securities, net of tax	348	133
Translation adjustments, net of tax	2,685	(2,185)
Other comprehensive income (loss)	3,033	(2,052)
Total consolidated comprehensive (loss) income	(6,310)	29,345
Net loss attributable to non-controlling interests	457	163
Comprehensive (loss) income attributable to NuVasive, Inc.	$ (5,853)	$ 29,508

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Operating activities:
Consolidated net (loss) income	$ (9,343)	$ 31,397
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	21,224	16,051
Loss on repurchases of convertible notes	17,444
Amortization of non-cash interest	5,112	4,331
Stock-based compensation	4,492	7,611
Reserves on current assets	4,162	633
Other non-cash adjustments	3,491	6,172
Deferred income taxes	1,794	11,015
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	6,939	5,931
Inventory	(9,449)	(11,367)
Prepaid expenses and other current assets	1,303	444
Accounts payable and accrued liabilities	10,040	17,428
Accrued royalties	(19)	(47,459)
Accrued payroll and related expenses	(9,219)	(10,163)
Litigation liability		7,730
Income taxes	9,421	(13,731)
Net cash provided by operating activities	57,392	26,023
Investing activities:
Acquisition of Ellipse Technologies, net of cash acquired	(380,674)
Other acquisitions and investments	(8,079)	(1,357)
Purchases of intangible assets	(1,027)	(27,389)
Purchases of property and equipment	(18,279)	(30,694)
Purchases of marketable securities	(36,096)	(71,129)
Proceeds from sales of marketable securities	253,435	105,794
Purchases of restricted investments		(32,616)
Net cash used in investing activities	(190,720)	(57,391)
Financing activities:
Incremental tax benefits related to stock-based compensation awards		8,092
Proceeds from the issuance of common stock	444	1,403
Payment of contingent consideration		(514)
Purchase of treasury stock	(12,599)	(30,944)
Proceeds from issuance of convertible debt, net of issuance costs	634,140
Proceeds from sale of warrants	44,850
Purchase of convertible note hedge	(111,150)
Repurchases of convertible notes	(343,835)
Proceeds from revolving line of credit	50,000
Repayments on revolving line of credit	(50,000)
Other financing activities	(1,442)	(45)
Net cash provided by (used in) financing activities	210,408	(22,008)
Effect of exchange rate changes on cash	686	(517)
Increase (decrease) in cash and cash equivalents	77,766	(53,893)
Cash and cash equivalents at beginning of period	192,339	142,387
Cash and cash equivalents at end of period	$ 270,105	$ 88,494

Description of Business and Bas

Description of Business and Basis of Presentation	3 Months Ended
	Mar. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business and Basis of Presentation	1. Description of Business and Basis of Presentation Description of Business NuVasive, Inc. (the “Company” or “NuVasive”) was incorporated in Delaware on July 21, 1997, and began commercializing its products in 2001. The Company’s principal product offering includes a minimally-disruptive surgical platform called Maximum Access Surgery, or MAS. The MAS platform combines three categories of solutions that collectively minimize soft tissue disruption during spine fusion surgery, provide maximum visualization and are designed to enable safe and reproducible outcomes for the surgeon and the patient. The platform includes our proprietary software-driven nerve detection and avoidance systems, NVM5, and Intraoperative Monitoring (“IOM”), services and support; MaXcess, an integrated split-blade retractor system; and a wide variety of specialized implants and biologics. The Company also recently launched Integrated Global Alignment (“iGA”), in which products and computer assisted technology under the MAS platform help achieve more precise spinal alignment. The individual components of the MAS platform, and many of the Company’s products, can also be used in open or traditional spine surgery. The Company continues to focus research and development efforts to expand its MAS product platform and advance the applications of its unique technology into procedurally-integrated surgical solutions. The Company dedicates significant resources toward training spine surgeons on its unique technology and products. The Company’s primary business model is to loan its MAS systems to surgeons and hospitals that purchase implants, biologics and disposables for use in individual procedures. In addition, for larger customers, the Company’s proprietary nerve monitoring systems, MaXcess and surgical instrument sets are placed with hospitals for an extended period at no up-front cost to them. The Company also offers a range of bone allograft in patented saline packaging, disposables and spine implants, which include its branded CoRoent ® On February 11, 2016 the Company acquired Ellipse Technologies, Inc. (“Ellipse Technologies”), which now operates as a wholly owned subsidiary under the renamed legal entity NuVasive Specialized Orthopedics, Inc. (“NSO”). NSO designs and sells expandable growing rod implant systems that can be non-invasively lengthened following implantation with precise, incremental adjustments via an external remote controller using magnetic technology called MAGnetic External Control, or MAGEC. The technology platform provides the basis of NSO’s core product offerings, including MAGEC-EOS, which allows for the minimally invasive treatment of early-onset and adolescent scoliosis, as well as PRECICE limb lengthening system, which allows for the correction of long bone limb length discrepancy, as well as enhanced bone healing in patients that have experienced traumatic injury. The Company intends to continue development on a wide variety of projects intended to broaden surgical applications for greater procedural integration of its MAS techniques and additional applications of the MAGEC technology. Such applications include tumor, trauma, and deformity, as well as increased fixation options and sagittal alignment products. The Company also expects to continue expanding its other product and services offerings as it executes on its strategy to offer customers an end-to-end, integrated procedural solution for spine surgery that distinguishes the Company from traditional spine implant companies. Basis of Presentation and Principles of Consolidation The accompanying Unaudited Consolidated Financial Statements include the accounts of the Company and its majority-owned or controlled subsidiaries, collectively referred to as either NuVasive or the Company. The Company translates the financial statements of its foreign subsidiaries using end-of-period exchange rates for assets and liabilities and average exchange rates during each reporting period for results of operations. When there is a portion of equity in an acquired subsidiary not attributable, directly or indirectly, to the respective parent entity, the Company records the fair value of the non-controlling interests at the acquisition date and classifies the amounts attributable to non-controlling interests separately in equity in the Company's consolidated financial statements. Any subsequent changes in a parent's ownership interest while the parent retains its controlling financial interest in its subsidiary are accounted for as equity transactions. All significant intercompany balances and transactions have been eliminated in consolidation. The accompanying Unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Pursuant to these rules and regulations, the Company has condensed or omitted certain information and footnote disclosures it normally includes in its annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Operating results for the three months ended March 31, 2016 are not necessarily indicative of the results that may be expected for any other interim period or for the full year. These Unaudited Consolidated Financial Statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2015 included in the Company’s Annual Report on Form 10-K filed with the SEC. In the opinion of management, the Unaudited Consolidated Financial Statements include all adjustments that are of a normal and recurring nature that are necessary for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The Company has reclassified historically presented product offerings revenue to conform to the current year presentation. The reclassification had no impact on previously reported results of operations or financial position Change in Accounting Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates. Recent Accounting Pronouncements Not Yet Adopted In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers In January 2016, the FASB issued Accounting Standards Update No. 2016-01, Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities In February 2016, the FASB issued new guidance related to leases that outlines a comprehensive lease accounting model and supersedes the current lease guidance. The new guidance requires lessees to recognize lease liabilities and corresponding right-of-use assets for all leases with lease terms of greater than 12 months. It also changes the definition of a lease and expands the disclosure requirements of lease arrangements. The new guidance must be adopted using the modified retrospective approach and will be effective for the Company starting in the first quarter of fiscal 2019. Early adoption is permitted. The Company is in the process of determining the effects the adoption will have on its consolidated financial statements as well as whether to adopt the new guidance early. In March 2016, the FASB issued Accounting Standards Update 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which amends ASC Topic 718, Compensation – Stock Compensation. ASU 2016-09 includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements. ASU 2016-09 is effective for public entities for annual reporting periods beginning after December 15, 2016, and interim periods within that reporting period. Early adoption is permitted in any interim or annual period, with any adjustments reflected as of the beginning of the fiscal year of adoption. The Company is evaluating the impact of this standard on its financial statements. Recently Adopted Accounting Standards In April 2014, the FASB issued ASU No. 2015-03 amended requirements that require debt issuance costs, related to a recognized debt liability, to be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, effective for the Company beginning January 1, 2016 applied retroactively for all consolidated balance sheets presented. The Company applied the amended presentation requirements in the first quarter 2016, which does not have a material impact on its financial statements. This change resulted in a reclassification from other assets to senior convertible notes on the Consolidated Balance Sheets presented. See Note 6 to the Unaudited Consolidated Financial Statements for revised presentation. Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) includes unrealized gains or losses on the Company’s marketable securities and foreign currency translation adjustments. The cumulative translation adjustments included in accumulated other comprehensive income (loss) were a net cumulative loss of $9.1 million and $11.6 million at March 31, 2016 and December 31, 2015, respectively. Business Transition Costs The Company incurs costs related to integration and business transition activities which include severance, relocation, consulting, and other costs directly associated to such activities. During the three months ended March 31, 2016, the business transition costs were immaterial to the results of operations. During the three months ended March 31, 2015, the Company incurred $5.4 million of such costs, which included a $3.4 million charge associated with the resignation of the Company’s former Chief Executive Officer and Chairman of the Board, which occurred in the first quarter 2015. The $3.4 million charge includes certain severance and compensation-related charges, net of certain forfeitures of previously recognized equity-based compensation. Product Shipment Costs Product shipment costs are included in sales, marketing and administrative expense in the accompanying Consolidated Statements of Operations were $6.2 million and $5.1 million for the three months ended March 31, 2016 and March 31, 2015, respectively. The majority of the Company’s shipping costs are related to the loan of instrument sets, which are not sold as part of the Company’s core sales offering. Amounts billed to customers for shipping and handling of products are reflected in revenues and are not significant for any period presented. Restructuring Charges During the three months ended March 31, 2015, the Company recognized incremental restructuring and associated impairment charges of $2.3 million associated with exiting its New Jersey location and termination of the respective lease. The Company previously exited a portion of the facility, in the first quarter of 2014, and this represents the exit from the entire facility. The restructuring and impairment charges mainly consist of the future rental payments through 2017, net of estimated future sublease income, and elimination of related leasehold improvements and deferred rent liabilities. These charges were recorded As of March 31, 2016, the total recorded liability associated with this early lease termination was $3.6 million compared to $4.1 million at December 31, 2015. The liability consists of future rental payments net of estimated sublease income through 2017. The current portion of the liability is recorded within accounts payable and accrued liabilities and the long-term portion is recorded within other long-term liabilities in the Consolidated Balance Sheets for the periods presented. Litigation Liability Gain During the three months ended March 31, 2015, the Company recorded a litigation liability gain of $42.6 million resulting primarily from the recognition of a $56.4 million gain stemming from a favorable appeal in Phase 1 of the Medtronic litigation, partially offset by a litigation loss of $13.8 million in connection with the OIG investigation. There were no material litigation gains or losses recorded during the three months ended March 31, 2016. See Note 11 and Note 12 to the Unaudited Consolidated Financial Statements for further discussion.

Net (Loss) Income Per Share

Net (Loss) Income Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Net (Loss) Income Per Share	2. Net (Loss) Income Per Share The following table sets forth the computation of basic and diluted (loss) income per share attributable to the Company: Three Months Ended March 31, ( in thousands, except per share data 2016 2015 Numerator: Net (loss) income available to the Company $ (8,886 ) $ 31,560 Denominator for basic and diluted net (loss) income per share: Weighted average common shares outstanding for basic 49,617 47,989 Dilutive potential common stock outstanding: Stock options and employee stock purchase plan — 1,528 Restricted stock units — 1,308 Warrants — — Senior Convertible Notes — 891 Weighted average common shares outstanding for diluted 49,617 51,716 Basic net (loss) income per share attributable to the Company $ (0.18 ) $ 0.66 Diluted net (loss) income per share attributable to the Company $ (0.18 ) $ 0.61 The following weighted outstanding common stock equivalents were not included in the calculation of net (loss) income per diluted share because their effects were anti-dilutive: Three Months Ended March 31, ( in thousands 2016 2015 Stock options, employee stock purchase plan, and restricted stock units 3,647 22 Warrants 20,418 9,553 Senior Convertible Notes 19,336 - Total 43,401 9,575

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	3 Months Ended
	Mar. 31, 2016
Investments Debt And Equity Securities [Abstract]
Financial Instruments and Fair Value Measurements	3. Financial Instruments and Fair Value Measurements The Company maintains an investment policy that requires a diversified investment portfolio in terms of types, maturities, and credit exposure, and invests with institutions that have high credit quality. Annually, the Company reassesses the investment policy to ensure it is reflective of current markets and conditions. The Company does not currently hold financial instruments for speculative purposes. The composition of marketable securities is as follows: ( in thousands, except years Contractual Maturity (in years) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value March 31, 2016: Classified as current assets Corporate notes Less than 1 $ 18,622 $ 12 $ (4 ) $ 18,630 Commercial paper Less than 1 23,865 — — 23,865 Short-term marketable securities 42,487 12 (4 ) 42,495 Classified as non-current assets Securities of government-sponsored entities 1 to 2 10,590 11 — 10,601 Corporate notes 1 to 2 7,772 10 (2 ) 7,780 Long-term marketable securities 18,362 21 (2 ) 18,381 Total marketable securities at March 31, 2016 $ 60,849 $ 33 $ (6 ) $ 60,876 December 31, 2015: Classified as current assets Certificates of deposit Less than 1 $ 6,615 $ — $ — $ 6,615 Corporate notes Less than 1 108,739 5 (173 ) 108,571 Commercial paper Less than 1 21,991 — — 21,991 Securities of government-sponsored entities Less than 1 28,284 — (38 ) 28,246 Short-term marketable securities 165,629 5 (211 ) 165,423 Classified as non-current assets Certificates of deposit 1 to 2 12,392 — — 12,392 Corporate notes 1 to 2 43,857 — (109 ) 43,748 Securities of government-sponsored entities 1 to 2 56,412 — (220 ) 56,192 Long-term marketable securities 112,661 — (329 ) 112,332 Total marketable securities at December 31, 2015 $ 278,290 $ 5 $ (540 ) $ 277,755 As of March 31, 2016, the Company had no investments that were in a significant unrealized loss position and no impairment charges were recorded during the periods presented. Realized gains and losses and interest income related to marketable securities were immaterial during all periods presented. Foreign Currency and Derivative Financial Instruments The Company translates the financial statements of its foreign subsidiaries using end-of-period exchange rates for assets and liabilities and average exchange rates during each reporting period for results of operations. Some of the Company’s reporting entities conduct a portion of their business in currencies other than the entity’s functional currency. These transactions give rise to receivables and payables that are denominated in currencies other than the entity’s functional currency. The value of these receivables and payables is subject to changes in currency exchange rates from the point at which the transactions are originated until the settlement in cash. Both realized and unrealized gains and losses in the value of these receivables and payables are included in the determination of net income. Net foreign currency exchange gains, which include gains and losses from derivative instruments, was $0.1 million for the three months ended March 31, 2016, and $0.3 million for the three months ended March 31, 2015, and are included in other income (expense) in the Consolidated Statements of Operations. The Company maintains a foreign currency risk management strategy that uses derivative instruments to protect against fluctuations in earnings and cash flows that may rise from volatility in currency exchange rates. The Company uses foreign currency forward exchange contracts to hedge the currency exchange rate exposure from short-term intercompany receivables and payables denominated in a currency other than the reporting entity’s functional currency. Realized and unrealized gains or losses on forward contracts are included in the determination of net income as the forward contracts are not designated for hedge accounting under ASC Topic 815, Derivatives and Hedging. A December 31, 2015, 8.5 million, respectively, . The following table summarizes the fair values of derivative instruments at March 31, 2016 and December 31, 2015: Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet March 31, December 31, Balance Sheet March 31, December 31, ( in thousands Location 2016 2015 Location 2016 2015 Derivative instruments not designated as cash flow hedges Forward exchange contracts Other current assets $ — * Other current liabilities $ 120 — Total derivatives $ — * $ 120 — *De minimis amount recognized in the hedge relationship. The following table summarizes the effect of derivative instruments on the Consolidated Statements of Operations for the three months ended March 31, 2016 and March 31, 2015: Three Months Ended Three Months Ended March 31, 2016 March 31, 2015 Location of Amount of Location of Amount of (Gain)/Loss (Gain)/Loss (Gain)/Loss (Gain)/Loss Recognized in Recognized in Recognized in Recognized in ( in thousands Income Income Income Income Derivative instruments not designated as cash flow hedges Forward exchange contracts Other (income) expense $ 179 Other (income) expense $ (2,165 ) Total derivatives $ 179 $ (2,165 ) Fair Value Measurements The Company measures certain assets and liabilities in accordance with authoritative guidance which requires fair value measurements be classified and disclosed in one of the following three categories: Level 1: Quoted prices (unadjusted) in active markets that are accessible at the measurement date for assets or liabilities. Level 2: Observable prices that are based on inputs not quoted on active markets, but corroborated by market data. Level 3: Unobservable inputs are used when little or no market data is available. Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. The Company reviews the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels for certain assets or liabilities within the fair value hierarchy. The fair values of the Company’s assets and liabilities, including cash equivalents, marketable securities, restricted investments, derivatives, and contingent consideration liabilities are measured at fair value on a recurring basis, and are determined under the fair value categories in accordance with the authoritative guidance as follows: Quoted Price in Significant Other Significant Active Market Observable Inputs Unobservable ( in thousands Total (Level 1) (Level 2) Inputs (Level 3) March 31, 2016: Money market funds $ 217,466 $ 217,466 $ — $ — Corporate notes 26,410 — 26,410 — Commercial paper 23,865 — 23,865 — Securities of government-sponsored entities 10,601 — 10,601 — Total assets $ 278,342 $ 217,466 $ 60,876 $ — December 31, 2015: Money market funds $ 68,425 $ 68,425 $ — $ — Certificates of deposit 19,007 19,007 — — Corporate notes 152,319 — 152,319 — Commercial paper 21,991 — 21,991 — Securities of government-sponsored entities 115,929 — 115,929 — Total assets $ 377,671 $ 87,432 $ 290,239 $ — The Company did not have any transfers of assets and liabilities between the levels of the fair value measurement hierarchy during the three months ended March 31, 2016. The carrying amounts of certain financial instruments such as cash equivalents, accounts receivable, prepaid expenses, other current assets, accounts payable, accrued expenses, and other current liabilities as of March 31, 2016 and December 31, 2015 approximate their related fair values due to the short-term maturities of these instruments. The carrying values of the Company’s capital lease obligations approximate their related fair values as of March 31, 2016 and December 31, 2015. The fair value, based on a quoted market price (Level 1), of the Company’s outstanding Senior Convertible Notes due 2017 at March 31, 2016 and December 31, 2015 were approximately $159.2 million and $551.4 million, respectively. The fair value, based on a quoted market price (Level 1), of the Company’s outstanding Senior Convertible Notes due 2021 was $696.7 million at March 31, 2016. See Note 6 to the Unaudited Consolidated Financial Statements for further discussion on the carrying value of the Company’s Senior Convertible Notes. Contingent Consideration Liability The following table sets forth the changes in the estimated fair value of the Company’s liabilities measured on a recurring basis using significant unobservable inputs (Level 3): Three Months Ended March 31, ( in thousands 2016 2015 Fair value measurement at beginning of period $ — $ 644 Contingent consideration liability recorded upon acquisition 21,439 — Change in fair value measurement included in operating expenses — (36 ) Contingent consideration paid or settled — (608 ) Fair value measurement at end of period $ 21,439 $ — The fair value of contingent consideration liabilities assumed in business combinations is determined using a discounted cash flow model, the significant inputs of which are not observable in the market. The fair value of such contingent considerations is recorded as part of the purchase consideration of the acquisition. The key assumptions in applying this approach are the projections associated with the applicable milestone, the interest rate and the related probabilities and payment structure in the contingent consideration arrangement. Contingent consideration arrangements assumed by an asset purchase will be measured and accrued when such contingency is resolved. During the first quarter of 2016, the Company recorded $21.4 million in contingent consideration liabilities as part of the purchase consideration of the acquisitions completed during the quarter. The liabilities are recorded in the Consolidated Balance Sheet, commensurate with the respective payable terms, as of March 31, 2016. See Note 5 to the Unaudited Consolidated Financial Statement for further discussion on contingent consideration liabilities assumed in business combinations. Non-financial assets and liabilities measured on a nonrecurring basis Certain non-financial assets and liabilities are measured at fair value, usually with Level 3 inputs including discounted cash flow method or cost method, on a nonrecurring basis in accordance with authoritative guidance. In general, non-financial assets, including intangible assets and property and equipment, are measured at fair value when there is an indication of impairment and are recorded at fair value only when any impairment is recognized. Any impairment charges recognized in the Consolidated Statements of Operations were immaterial for the periods presented.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	4. Goodwill and Intangible Assets Goodwill and intangible assets consisted of the following: Weighted- Average Amortization ( in thousands, except years Period Gross Accumulated Intangible March 31, 2016: (in years) Amount Amortization Assets, net Intangible assets subject to amortization: Developed technology 8 $ 226,548 $ (43,389 ) $ 183,159 Manufacturing know-how and trade secrets 12 21,817 (13,707 ) 8,110 Trade name and trademarks 9 25,700 (5,653 ) 20,047 Customer relationships 9 84,436 (29,663 ) 54,773 Total intangible assets subject to amortization 8 $ 358,501 $ (92,412 ) $ 266,089 Intangible assets not subject to amortization: Goodwill $ 404,307 Total goodwill and intangible assets, net $ 670,396 Weighted- Average Amortization Period Gross Accumulated Intangible December 31, 2015: (in years) Amount Amortization Assets, net Intangible assets subject to amortization: Developed technology 9 $ 92,648 $ (37,382 ) $ 55,266 Manufacturing know-how and trade secrets 12 21,787 (13,296 ) 8,491 Trade name and trademarks 11 9,500 (5,068 ) 4,432 Customer relationships 8 44,752 (27,865 ) 16,887 Total intangible assets subject to amortization 10 $ 168,687 $ (83,611 ) $ 85,076 Intangible assets not subject to amortization: Goodwill $ 154,281 Total goodwill and intangible assets, net $ 239,357 During the three months ended March 31, 2016, in connection with acquisitions and other investments, the Company recorded additions to definite-lived intangible assets and goodwill of $189.8 million and $250.0 million, respectively. See Note 5 to the Unaudited Consolidated Financial Statement for further discussion on assets acquired in business combinations and asset acquisitions. The following table summarizes the changes in the carrying value of the Company’s goodwill: Three Months Ended March 31, ( in thousands 2016 2015 Goodwill at beginning of period $ 154,281 $ 154,443 Increases recorded in business combinations 249,973 — Changes resulting from foreign currency fluctuations 53 (170 ) Goodwill at end of period $ 404,307 $ 154,273 Total expense related to the amortization of intangible assets, which is recorded in both cost of goods sold and operating expenses in the Consolidated Statements of Operations, was $8.8 million and $3.9 million for the three months ended March 31, 2016 and March 31, 2015, respectively. Total future amortization expense related to intangible assets subject to amortization at March 31, 2016 is set forth in the table below: ( in thousands Remaining 2016 $ 33,232 2017 41,114 2018 39,228 2019 37,749 2020 37,338 2021 35,477 Thereafter through 2027 41,951 Total future amortization expense $ 266,089

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2016
Business Combination Description [Abstract]
Business Combinations	5. Business Combinations The Company recognizes the assets acquired, liabilities assumed, and any non-controlling interest at fair value at the date of acquisition. Certain acquisitions contained contingent consideration arrangements that required the Company to assess the acquisition date fair value of the contingent consideration liabilities, which was recorded as part of the purchase consideration of the acquisition with subsequent fair value adjustments to the contingent consideration recorded in the Consolidated Statements of Operations commensurate with the nature of the contingent consideration. Acquisition of Ellipse Technologies, Inc. On February 11 NSO designs and sells expandable growing rod implant systems that can be non-invasively lengthened following implantation with precise, incremental adjustments via an external remote controller using magnetic technology called MAGnetic External Control, or MAGEC. The technology platform provides the basis of NSO’s core product offerings, including MAGEC-EOS, which allows for the minimally invasive treatment of early-onset and adolescent scoliosis, as well as PRECICE limb lengthening system, which allows for the correction of long bone limb length discrepancy, as well as enhanced bone healing in patients that have experienced traumatic injury. The Company is still in the process of finalizing the purchase price allocation given the timing of the acquisition and the size and scope of the assets and liabilities subject to valuation. While the Company does not expect material changes in the valuation outcome, certain assumptions and findings that were in place at the date of acquisition could result in changes in the purchase price allocation. The allocation of the purchase price to the assets acquired and liabilities assumed based on their fair values was as follows: ( in thousands Cash paid for purchase $ 382,174 Accounts receivable 7,148 Inventory 22,451 Other current assets 1,855 Property, plant and equipment, net 6,725 Definite-lived intangible assets: Developed technology 133,900 Customer relationships 33,200 Trade names 16,200 Goodwill 242,675 Deferred tax assets 17,694 Other assets 1,868 Contingent consideration liability 18,800 Deferred tax liabilities 75,999 Other liabilities assumed 6,743 $ 382,174 Goodwill recognized in this transaction is not deductible for tax purposes. Goodwill largely consists of expected revenue synergies resulting from the combination of product portfolios, cost synergies related to elimination of redundant facilities, functions and staffing; use of the Company’s existing commercial infrastructure to expand sales of NSO’s products; In connection with the acquisition, a contingent liability of $18.8 million was recorded for the potential revenue-based milestone payment. The liability was fair valued using the Monte Carlo simulation based on specific revenue achievement scenarios and discount factors. Changes in fair value of the liability over the measurement period will be recorded in the results of operations in the Consolidated Statements of Operations. Acquisition costs of $4.0 million were recognized as selling, marketing and administrative expenses as incurred. The Company’s results of operations for the three months ended March 31, 2016 included the operating results of NSO since the date of acquisition, of $5.8 million of revenue and net loss of $1.6 million in the Unaudited Consolidated Statement of Operations. The following table presents the unaudited pro forma results for the three months ended March 31, 2016 and March 31, 2015. The unaudited pro forma financial information combines the results of operations of NuVasive and Ellipse Technologies as though the companies had been combined as of January 1, 2015, and the pro forma information is presented for informational purposes only and is not indicative of the results of operations that would have been achieved if the acquisition had taken place at such times. The unaudited pro forma results presented include non-recurring adjustments directly attributable to the business combination, including $6.5 million in amortization charges for acquired intangible assets, a $7.4 million adjustment for increased fair value of acquired inventory, $0.1 million reduction to revenue for deferred revenue adjustments, $4.0 million in acquisition related expenses, Three Months Ended March 31, ( in thousands, except per share amounts 2016 2015 Revenues $ 221,012 $ 200,636 Net (loss) income attributable to NuVasive, Inc. (6,013 ) 18,140 Net (loss) income per share attributable to NuVasive, Inc.: Basic $ (0.12 ) $ 0.38 Diluted $ (0.12 ) $ 0.35 Other Acquisitions The Company has completed other acquisitions that were not considered individually or collectively material to the overall Unaudited Consolidated Financial Statements during the periods presented. These acquisitions have been included in the Unaudited Consolidated Financial Statements from the respective dates of acquisition. For certain acquisitions, the Company is still in the process of finalizing the purchase price allocation given the timing of the acquisition and the size and scope of the assets and liabilities subject to valuation. While the Company does not expect material changes in the valuation outcome, certain assumptions and findings that were in place at the date of acquisition could result in changes in the purchase price allocation. Variable Interest Entities Progentix Orthobiology B.V. In 2009, the Company completed the purchase of 40% of the capital stock of Progentix In accordance with authoritative guidance, the Company has determined that Progentix is a variable interest entity (“VIE”), as it does not have the ability to finance its activities without additional subordinated financial support and its equity investors will not absorb their proportionate share of expected losses and will be limited in the receipt of the potential residual returns of Progentix. Total assets and liabilities of Progentix included in the accompanying Consolidated Balance Sheets are as follows: ( in thousands March 31, 2016 December 31, 2015 Total current assets $ 358 $ 353 Identifiable intangible assets, net 12,511 13,048 Goodwill 12,654 12,654 Accounts payable and accrued expenses 714 574 Deferred tax liabilities, net 1,304 1,496 Non-controlling interests 6,852 7,309 The following is a reconciliation of equity (net assets) attributable to the non-controlling interests: Three Months Ended March 31, ( in thousands 2016 2015 Non-controlling interests at beginning of period $ 7,309 $ 8,310 Less: Net loss attributable to the non-controlling interests 457 163 Non-controlling interests at end of period $ 6,852 $ 8,147 Impulse Monitoring, Inc. and Physician Practices The Company maintains contractual relationships with several physician practices (“PCs”) which were inherited through the 2011 acquisition of Impulse Monitoring, Inc. In accordance with authoritative guidance, the Company has determined that the PCs are VIEs and the therefore, the accompanying Consolidated Financial Statements include the accounts of the PCs from the date of acquisition. During the periods presented, the result of PCs was immaterial to the Company’s financials. The creditors of the PCs have claims only on the assets of the PCs, which are not material, and the assets of the PCs are not available to the Company.

Indebtedness

Indebtedness	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Indebtedness	6. Indebtedness The carrying values of the Company’s Senior Convertible Notes are as follows: ( in thousands March 31, 2016 December 31, 2015 2.75% Senior Convertible Notes due 2017: Principal amount $ 125,732 $ 402,500 Unamortized debt discount (6,818 ) (25,958 ) Unamortized debt issuance costs (957 ) (3,622 ) 117,957 372,920 2.25% Senior Convertible Notes due 2021: Principal amount 650,000 — Unamortized debt discount (84,144 ) — Unamortized debt issuance costs (14,415 ) — 551,441 — Total Senior Convertible Notes $ 669,398 $ 372,920 2.25% Senior Convertible Notes due 2021 In March 2016, the Company issued $650.0 million principal amount of unsecured Senior Convertible Notes with a stated interest rate of 2.25% and a maturity date of March 15, 2021 (the "2021 Notes"). The net proceeds from the offering, after deducting initial purchasers' discounts and costs directly related to the offering, were approximately $634.1 million. The 2021 Notes may be settled in cash, stock, or a combination thereof, solely at the Company's discretion. It is the Company's current intent and policy to settle all conversions through combination settlement, which involves satisfying the principal amount outstanding with cash and any note conversion value over the principal amount in shares of the Company's common stock. The initial conversion rate of the 2021 Notes is 16.7158 shares per $1,000 principal amount, which is equivalent to a conversion price of approximately $59.82 per share, subject to adjustments. The Company uses the treasury share method for assumed conversion of the 2021 Notes to compute the weighted average shares of common stock outstanding for diluted earnings per share. The Company also entered into transactions for convertible note hedge (the "2021 Hedge") and warrants (the "2021 Warrants") concurrently with the issuance of the 2021 Notes. The cash conversion feature of the 2021 Notes (the “Embedded Conversion Derivative”) required bifurcation from the Notes and was initially accounted for as an equity instrument classified to stockholders’ equity, which resulted in recognizing $84.8 million in additional paid-in-capital during 2016. The interest expense recognized on the 2021 Notes during the three month period ended March 31, 2016 includes $0.6 million, $0.6 million and $0.1 million for the contractual coupon interest, the accretion of the debt discount and the amortization of the debt issuance costs, respectively. The effective interest rate on the 2021 Notes is 5.8%, which includes the interest on the notes, amortization of the debt discount and debt issuance costs. Interest on the 2021 Notes began accruing upon issuance and is payable semi-annually. Prior to September 15, 2020, holders may convert their 2021 Notes only under the following conditions: (a) during any calendar quarter beginning June 30, 2016, if the reported sale price of the Company's common stock for at least 20 days out of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than 130% of the conversion price on each applicable trading day; (b) during the five business day period in which the trading price of the 2021 Notes falls below 98% of the product of (i) the last reported sale price of the Company's common stock and (ii) the conversion rate on that date; and (c) upon the occurrence of specified corporate events, as defined in the 2021 Notes. From September 15, 2020 and until the close of business on the second scheduled trading day immediately preceding March 15, 2021, holders may convert their 2021 Notes at any time (regardless of the foregoing circumstances). The Company may not redeem the 2021 Notes prior to March 20, 2019. The Company may redeem the 2021 Notes, at its option, in whole or in part on or after March 20, 2019 until the close of business on the business day immediately preceding September 15, 2020 if the last reported sale price of the Company’s common stock has been at least 130% of the conversion price then in effect for at least 20 trading days during any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which the Company delivers written notice of a redemption. The redemption price will be equal to 100% of the principal amount of such 2021 Notes to be redeemed plus accrued and unpaid interest to, but excluding, the redemption date 2021 Hedge In connection with the offering of the 2021 Notes, the Company entered into the hedge transaction with the initial purchasers and/or their affiliates (the "2021 Counterparties") entitling the Company to purchase up to 10,865,270 shares of the Company's common stock at an initial stock price of $59.82 per share, each of which is subject to adjustment. The cost of the 2021 Hedge was $111.2 million and accounted for as equity instrument by recognizing $111.2 million in additional paid-in-capital during 2016. The 2021 Hedge will expire on March 15, 2021. The 2021 Hedge is expected to reduce the potential equity dilution upon conversion of the 2021 Notes if the daily volume-weighted average price per share of the Company's common stock exceeds the strike price of the 2021 Hedge. An assumed exercise of the 2021 Hedge by the Company is considered anti-dilutive since the effect of the inclusion would always be anti-dilutive with respect to the calculation of diluted earnings per share. 2021 Warrants The Company sold warrants to the 2021 Counterparties to acquire up to 10,865,270 shares of the Company’s common stock. The 2021 Warrants will expire on various dates from June 2021 through December 2021 and may be settled in cash or net shares. It is the Company's current intent and policy to settle all conversions in shares of the Company’s common stock. The Company received $44.9 million in cash proceeds from the sale of the 2021 Warrants, which was recorded in additional paid-in-capital. The 2021 Warrants could have a dilutive effect on the Company's earnings per share to the extent that the price of the Company's common stock during a given measurement period exceeds the strike price of the 2021 Warrants, which is $80.00 per share. The Company uses the treasury share method for assumed conversion of its 2021 Warrants to compute the weighted average common shares outstanding for diluted earnings per share. 2.75% Senior Convertible Notes due 2017 In June 2011, the Company issued $402.5 million 2.75% July 1, 2017 $359.2 million 23.7344 $1,000 $42.13 The cash conversion feature of the 2017 Notes (the “Embedded Conversion Derivative”) required bifurcation from the Notes and was initially accounted for as a derivative liability and debt discount of $88.9 million upon issuance of the Notes without authorization of issuing additional common stocks for the conversion. Upon obtaining stockholder approval for the additional authorized shares of the Company’s common stock, the derivative liability was reclassified to stockholders’ equity, which resulted in recognizing cumulatively $39.5 million in other income for change in fair value measurement and $49.4 million in additional paid-in-capital during 2011. The interest expense recognized on the 2017 Notes during the three month period ended March 31, 2016 includes $2.5 million, $3.7 million and $0.5 million for the contractual coupon interest, the accretion of the debt discount and the amortization of debt issuance costs, respectively. The interest expense recognized on the 2017 Notes during the three month period ended March 31, 2015 includes $2.8 million, $3.8 million and $0.5 million for the contractual coupon interest, the accretion of the debt discount and the amortization of debt issuance costs, respectively. The effective interest rate on the 2017 Notes is 8.0%, which includes the interest on the notes, amortization of the debt discount and debt issuance costs. Interest on the 2017 Notes began accruing upon issuance and is payable semi-annually. Prior to January 1, 2017, holders may convert their 2017 Notes only under the following conditions: (a) during any calendar quarter beginning October 1, 2011, if the reported sale price of the Company’s common stock for at least 20 30 130% five 98% 2017 Hedge In connection with the offering of the 2017 Notes, the Company entered into the 2017 Hedge with the initial purchasers and/or their affiliates (the “2017 Counterparties”) entitling the Company to purchase up to 9,553,096 $42.13 $80.1 million and accounted for as derivative assets upon issuance of the 2017 Notes additional paid-in-capital effect of inclusion would always be anti-dilutive with respect to the calculation of diluted earnings per share. 2017 Warrants The Company sold warrants to the 2017 Counterparties to acquire up to 477,654 $988.51 20 $47.9 million additional paid-in-capital Repurchases of Senior Convertible Notes due 2017 In March 2016, the Company used approximately $345.2 million of the net proceeds from the 2021 Notes offering to repurchase approximately $276.8 million principal amount outstanding of the $402.5 million principal Senior Convertible Notes due 2017, the associated conversion feature of the repurchased notes (which is recorded in additional paid-in capital), and the accrued interest on the repurchased notes. As a result of this repurchase the Company recorded a loss in other expense, on the accompanying Consolidated Statements of Operations, of approximately $17.4 million during the three months ended March 31, 2016 on the early extinguishment of 2017 Notes and related the debt issuance costs that were previously capitalized in connection with the issuance of the 2017 Notes. The repurchase of a portion of the 2017 Notes resulted in remaining balances of $125.7 million, $6.8 million, and $1.0 million of principal outstanding, debt discount, and debt issuance costs, respectively, as of March 31, 2016. The Company intends to use the remainder of the net proceeds from the 2021 Notes offering for general corporate purposes. Revolving Senior Credit Facility In February 2016, the Company entered into a Credit Agreement (the “Credit Agreement”) for a revolving senior credit facility (the “Facility”) that provides for secured revolving loans, multicurrency loan options and letters of credit in an aggregate amount of up to $150.0 million. The Credit Agreement also contains an expansion feature, which allows the Company to increase the aggregate principal amount of the Facility provided the Company remains in compliance with the underlying financial covenants. The Facility matures February 8, 2021, and includes a sub-limit of $15.0 million for letters of credit and a sub-limit of $5.0 million for swing line loans. All assets of the Company and its material domestic subsidiaries are pledged as collateral under the Facility (subject to customary exceptions) pursuant to the term set forth in the Security and Pledge Agreement (the “Security Agreement”) executed in favor of the administrative agent by the Company. Each of the Company’s material domestic subsidiaries guarantees the Facility. Borrowings under the Facility are used by us to provide financing for working capital and other general corporate purposes, including potential mergers and acquisitions. Loans under the Facility bear interest, at the option of the Company, at either LIBOR (determined in accordance with the Credit Agreement) plus an applicable margin ranging from 1.00 % - 2.00 % per annum subject to Company’s applicable consolidated leverage ratio or the Base Rate (determined in accordance with the Credit Agreement), plus an applicable margin ranging from 0.0% - 1.25% per annum subject to Company’s applicable consolidated leverage ratio. The Facility has a commitment fee, which accrues at a rate of 0.2% - 0.4% per annum (determined in accordance with the Credit Agreement) based on the Company’s current leverage ratio. The Credit Agreement contains affirmative, negative and financial covenants, and events of default customary for financings of this type. The financial covenants require the Company to maintain ratios of consolidated earnings before interest, taxes, depreciation and amortization (EBITDA) in relation to consolidated interest expense and consolidated debt, respectively, as defined in the Credit Agreement, at varying scales throughout the life of the Credit Agreement. The Facility grants the lenders preferred first priority liens and security interests in capital stock, intercompany debt and all of the present and future property and assets of the Company and each guarantor.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	7. Stock-Based Compensation The compensation cost that has been included in the Consolidated Statements of Operations for all stock-based compensation arrangements was as follows: Three Months Ended March 31, ( in thousands 2016 2015 Sales, marketing and administrative expense $ 4,430 $ 7,277 Research and development expense 10 259 Cost of goods sold 52 75 Stock-based compensation expense before taxes 4,492 7,611 Related income tax benefits (1,797 ) (3,044 ) Stock-based compensation expense, net of taxes $ 2,695 $ 4,567 At March 31, 2016, there was $56.1 million of unamortized compensation expense for restricted stock units (“RSUs”) and performance-based restricted stock units (“PRSUs”) to be recognized over a weighted average period of 2.7 years. Stock Options and Purchase Rights The weighted average assumptions used to estimate the fair value of stock purchase rights under the employee stock purchase plan (“ESPP”) are as follows: Three Months Ended March 31, 2016 2015 ESPP Volatility 31 % 44 % Expected term (years) 0.6 1.4 Risk free interest rate 0.3 % 0.2 % Expected dividend yield — % — % Under the terms of the ESPP, shareowners can elect to have up to 15% of their annual compensation, up to a maximum of $21,250 per year, withheld to purchase shares of the Company’s common stock for a purchase price equal to 85% of the lower of the fair market value per share (at closing) of the Company’s common stock on (i) the commencement date of the two-year or six-month offering period (depending on the purchase period enrolled), or (ii) the respective purchase date. The Company has not granted any options since 2011. The Company issued approximately 0.1 million shares of common stock, before net share settlement, upon the exercise of outstanding stock options during the three months ended March 31, 2016 and issued approximately 3.3 million shares of common stock upon the exercise of outstanding stock options during the year ended December 31, 2015. Restricted Stock Units The Company issued approximately 0.7 million shares of common stock, before net share settlement, upon vesting of RSUs (including PRSUs) during the three months ended March 31, 2016 and issued approximately 1.4 million shares of common stock in settlement of RSUs (including PRSUs) upon their vesting during the year ended December 31, 2015. Assumed Equity Incentive Plan In connection with the acquisition of Ellipse Technologies (see Note 5 to the Unaudited Consolidated Financial Statements), the Company assumed the Ellipse Technologies, Inc. 2015 Incentive Award Plan and the shares thereunder, subject to an equity exchange adjustment, for future awards by the Company.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes Income taxes are determined using an estimated annual effective tax rate applied against income, and then adjusted for the tax impacts of certain significant and discrete items. For the three months ended March 31, 2016, the tax effects for discrete events such as changes to the beginning of the year valuation allowances, certain unrecognized tax benefits, and return to provision adjustments were recognized separately from the application of the annual effective tax rate. The Company’s effective tax rate recorded for the three months ended March 31, 2016 was 30%. In accordance with the disclosure requirements as described in ASC Topic 740, Income Taxes, the Company has classified unrecognized tax benefits as non-current income tax liabilities, or a reduction in deferred tax assets, unless expected to be paid within one year. The Company’s continuing practice is to recognize interest and/or penalties related to income tax matters in income tax expense. The Company had an increase in gross unrecognized tax benefits of approximately $1.5 million during the three months ended March 31, 2016. The Company does not anticipate there will be a significant change in unrecognized tax benefits within the next 12 months. The Company is subject to routine compliance reviews on various tax matters around the world in the ordinary course of business. Currently, income tax audits are being conducted in the state of New York and the state of Louisiana. U.S. and most foreign jurisdictions remain subject to examination in all years due to prior year net operating losses and R&D credits. Upon the acquisition of Ellipse Technologies, the Company recorded a net deferred tax liability through goodwill of approximately $58.3 million primarily related to basis differences in the assigned fair value of acquired intangible assets. See Note 5 to the Unaudited Consolidated Financial Statements for further information regarding the acquisition.

Business Segment, Product, and

Business Segment, Product, and Geographic Information	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Business Segment, Product and Geographic Information	9. Business Segment, Product and Geographic Information The Company operates in one segment based upon the Company’s organizational structure, the way in which the operations are managed and evaluated by the chief operating decision maker (“CODM”) and the lack of availability of discrete financial information. The Company operates under two distinct product lines; spinal hardware and surgical support. The Company’s spinal hardware product line offerings include implants and fixation products, and following the acquisition of Ellipse Technologies, also include the MAGEC- EOS spinal bracing and lengthening system and the PRECICE limb lengthening system. The Company’s surgical support product offerings include IOM services, disposables and biologics, all of which are used to aid spinal surgery. Revenue by product line was as follows: Three Months Ended March 31, ( in thousands 2016 2015 Spinal Hardware $ 151,957 $ 131,222 Surgical Support 63,147 61,161 Total Revenue $ 215,104 $ 192,383 Revenue and property and equipment, net, by geographic area were as follows: Revenue Property and Equipment, Net Three Months Ended March 31, March 31, December 31, ( in thousands 2016 2015 2016 2015 United States $ 188,351 $ 169,926 $ 124,229 $ 113,037 International (excludes Puerto Rico) 26,753 22,457 28,759 28,404 Total $ 215,104 $ 192,383 $ 152,988 $ 141,441

Commitments

Commitments	3 Months Ended
	Mar. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments	10. Commitments Licensing and Purchasing Agreements As of March 31, 2016, the Company has obligations under certain consultancy arrangements to pay up to approximately $23.4 million in the aggregate in the event that specified revenue-based milestones are achieved prior to 2024. Any such payment will be made in a combination of cash and the Company’s common shares as provided in the agreements. Any payments in satisfaction of theses contingent obligations are considered a cost of goods sold and are recognized as and if milestones are achieved. These agreements expire on various dates through 2024. Executive Severance Plans The Company has employment contracts with key executives and maintains severance plans that provide for the payment of severance and other benefits if terminated for reasons other than cause, as defined in those agreements and plans. Certain agreements call for payments that are based on historical compensation, accordingly, the amount of the contractual commitment will change over time commensurate with the executive’s applicable earnings. At March 31, 2016, future commitments for such key executives were approximately $22.3 million. In certain circumstances, the agreements call for the acceleration of equity vesting. Those figures are not reflected in the above information. Leasing Commitments Assumed in Business Combinations In connection with the acquisition of Ellipse Technologies (see Note 5 to the Unaudited Consolidated Financial Statements for further information regarding the acquisition) the Company assumed the operating leases to its office facilities. The leases were determined to be of similar terms that would be expected to be provided to the Company had it entered into the leasing agreements independently. In connection with the operating leases, the Company acquired the security deposits recorded and maintained as restricted cash which total $1.5 million as of March 31, 2016. The Company’s future lease payment commitments total $7.5 million through the terms of the lease. The terms of the leases extend through 2020, and g enerally provide for periodic rent increases. Rent expense is recognized on a straight-line basis over the term of the lease. Accordingly, rent expense recognized in excess of rent paid is reflected as a liability in the accompanying Unaudited Consolidated Balance Sheets.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2016
Contingencies [Abstract]
Contingencies	11. Contingencies The Company is subject to potential liabilities under government regulations and various claims and legal actions that are pending or may be asserted from time-to-time. These matters arise in the ordinary course and conduct of the Company’s business and include, for example, commercial, intellectual property, environmental, securities and employment matters. The Company intends to continue to defend itself vigorously in such matters. Furthermore, the Company regularly assesses contingencies to determine the degree of probability and range of possible loss for potential accrual in its financial statements. The Company did not record any material litigation gains or losses in the three months ended March 31, 2016. During the three months ended March 31, 2015, the Company had a gain of $56.4 million related to a litigation accrual change resulting from the legal proceedings in Phase 1 of the Medtronic litigation whereby the damages award by the jury was overturned. This amount was offset by a litigation charge of $13.8 million related to the Office of the Inspector General of the U.S. Department of Health and Human Services (“OIG”) investigation. Refer to both the subsequent section herein titled “Legal Proceedings” and to Note 12 to the Unaudited Consolidated Financial Statements for further information. An estimated loss contingency is accrued in the Company’s financial statements if it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Based on the Company’s assessment, it has adequately accrued an amount for contingent liabilities currently in existence. The Company does not accrue amounts for liabilities that it does not believe are probable or that it considers immaterial to its overall financial position. Litigation is inherently unpredictable, and unfavorable resolutions could occur. As a result, assessing contingencies is highly subjective and requires judgment about future events. The amount of ultimate loss may exceed the Company’s current accruals, and it is possible that its cash flows or results of operations could be materially affected in any particular period by the unfavorable resolution of one or more of these contingencies. Legal Proceedings Medtronic Sofamor Danek USA, Inc. Litigation In August 2008, Warsaw Orthopedic, Inc., Medtronic Sofamor Danek USA, Inc. and other Medtronic related entities (collectively, “Medtronic”) filed a patent infringement lawsuit against the Company in the United States District Court for the Southern District of California (the “Medtronic Litigation”), alleging that certain of the Company’s products or methods, including the XLIF ® twelve Three nine The case has been administratively broken into several phases. The first phase (“Phase 1”) of the case included three one three one $101.2 million Both parties filed appeals to the U.S. Court of Appeals for the Federal Circuit. On March 2, 2015, the Court of Appeals issued a decision upholding the jury’s findings of liability as to all patents, but overturning the damage award against the Company as improper (“March 2 nd As a result of the affirmation of the infringement and remand for a new trial on damages, the Company assessed the existing liability under the loss contingency framework and – in accordance with applicable accounting guidance – believes the most appropriate accrual estimate within the possible range dictated by such guidance is $87.6 million. This amount represents liability for the infringement of the two Medtronic patents for infringing products at historically supplied rates from the date of infringement to the current period. The liability does not include an accrual for lost profits or convoyed products. A liability associated with this matter has been recorded in non-current litigation liabilities. In prior periods, the Company recorded the respective liabilities (as estimated) in non-current litigation liabilities and the accrued royalties in accrued liabilities. The Company does not agree with the previously-ruled royalty rates, and intends to rigorously pursue appropriate rates during the new trial on damages. Nonetheless, in the interim, the Company has applied the previously-ruled royalty rates when calculating the appropriate estimate. As a result of the adjustment, the Company recorded an adjustment of $56.4 million as a gain in its Consolidated Statements of Operations during the first quarter 2015. On March 19, 2012, in connection with these proceedings, the Company entered into an escrow arrangement and transferred $113.3 million nd In accordance with the authoritative guidance on the evaluation of loss contingencies, during the year ended December 31, 2011, the Company recorded an accrual of $101.2 million $7.9 million nd nd With respect to the favorable verdict delivered regarding the one Company patent litigated to verdict, the jury awarded the Company monetary damages of approximately $0.7 million $0.7 million The second phase of the case involved one Medtronic cervical plate patent. On April 25, 2013, the Company and Medtronic entered into a settlement agreement fully resolving the second phase of the case. The settlement also removed from the case the cervical plate patent that was part of the first phase. As part of the settlement, the Company received a broad license to practice (i) the Medtronic patent that was the sole subject of the second phase of the litigation, (ii) the Medtronic cervical plate patent that was part of the first phase of the litigation, and (iii) each of the Medtronic patent families that collectively represent the vast majority of Medtronic’s patent rights related to cervical plate technology. In exchange for these license rights, the Company made a one-time payment to Medtronic of $7.5 million In August 2012, Medtronic filed additional patent claims in the U.S. District Court for the Northern District of Indiana alleging that various Company spinal implants (including its CoRoent XL family of spinal implants) infringe Medtronic’s U.S. Patent No. 8,021,430, that the Company’s Osteocel Plus bone graft product infringes Medtronic’s U.S. Patent No. 5,676,146, (“146 Patent”) and that the Company’s XLIF procedure and use of MaXcess IV retractor during the XLIF procedure infringe methodology claims of Medtronic’s U.S. Patent No. 8,251,997. The case, which is referred to herein as the third phase of the Medtronic litigation, was later transferred to the Southern District of California, and, on March 7, 2013, the Company counterclaimed alleging infringement by Medtronic of the Company’s U.S. Patent Nos. 8,000,782 (systems and related methods for performing surgical procedures), 8,005,535 (systems and related methods for performing surgical procedures), 8,016,767 (a surgical access system including a tissue distraction assembly and a tissue retraction assembly), 8,192,356 (a system for accessing a surgical target site and related methods, involving an initial distraction system, among other things), 8,187,334 (spinal fusion implant), 8,361,156 (spinal fusion implant), D652,922 (dilator design) (“922 Patent”), and D666,294 (dilator design). On July 25, 2013, Medtronic amended its complaint to add a charge of infringement of its U.S. Patent No. 8,444,696. The District Court has stayed litigation of a number of Medtronic and Company patents currently subject to reexamination or review proceedings conducted by the Patent Office. Both parties brought motions for summary judgment addressing the patents that were not stayed or dismissed in the litigation. On October 20, 2015, the District Court issued an opinion granting Medtronic’s motion for summary judgment of non-infringement of the Company’s ‘922 Patent. Similarly, on February 17, 2016, the District Court granted the Company’s motion for summary judgment of non-infringement of Medtronic’s ‘146 Patent, and Medtronic has sought reconsideration of the Court’s ruling. No other patent infringement claims are currently active in Phase 3 of the litigation. At March 31, 2016, the probable outcome of this litigation cannot be determined, nor can the Company estimate a range of potential loss. In accordance with the authoritative guidance on the evaluation of loss contingencies, the Company has not recorded an accrual related to this litigation. Trademark Infringement Litigation On September 25, 2009, Neurovision Medical Products, Inc. (“NMP”) filed suit against the Company in the U.S. District Court for the Central District of California (Case No. 2:09-cv-06988-R-JEM) alleging trademark infringement and unfair competition. NMP sought cancellation of NuVasive’s “NeuroVision” trademark registrations, injunctive relief and damages based on NMP’s common law use of the “NeuroVision” mark. The matter was tried in October 2010 and an unfavorable jury verdict was delivered against the Company The verdict awarded damages to NMP of $60.0 million, and the Company appealed the judgment. The Court of Appeals reversed and vacated the judgment, and a new trial was conducted in the District Court. In April 2014, a jury returned a verdict in favor of NMP on its claims against the Company in the amount of $30.0 million. The District Court also entered an order canceling the Company’s NeuroVision trademark registrations. In July 2015, the Company agreed to settle all outstanding matters with NMP for $27.2 million. The Company adjusted its litigation accrual from $30.0 million to $27.2 million at June 30, 2015; resulting in a $2.8 million gain which was recorded in the Consolidated Statement of Operations during the three months ended June 30, 2015. The Company previously escrowed funds totaling $32.5 million to secure the amount of judgment, and cover potential attorney’s fees and costs. Those funds accrued interest and were included in short-term restricted cash and investments in the Consolidated Balance Sheets until funding of the settlement which occurred during the three months ended September 30, 2015. The Company no longer has any remaining liability or restricted cash related to this matter. Securities Litigation On August 28, 2013, a purported securities class action lawsuit was filed in the U.S. District Court for the Southern District of California naming the Company and certain of its current and former executive officers for allegedly making false and materially misleading statements regarding the Company’s business and financial results, specifically relating to the purported improper submission of false claims to Medicare and Medicaid. The complaint asserts a putative class period stemming from October 22, 2008 to July 30, 2013. The complaint alleges violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended, and Rule 10b-5 promulgated thereunder and seeks unspecified monetary relief, interest, and attorneys’ fees. On February 13, 2014, the lead plaintiff (“Plaintiff”) filed an Amended Class Action Complaint for Violations of the Federal Securities Laws. The District Court granted the Company’s motion to dismiss the Amended Complaint and ordered Plaintiff to amend its complaint. Plaintiff filed a Second Amended Complaint on September 8, 2014, and the District Court once again granted the Company’s motion to dismiss the complaint with leave to amend. On December 23, 2014, Plaintiff filed a Third Amended Complaint. The Company filed a motion to dismiss, and while the Company’s motion was pending, Plaintiff sought leave to file a Fourth Amended Complaint. The Company moved to dismiss the Fourth Amended Complaint. On August 28, 2015, the District Court issued an order granting the Company’s motion to dismiss the Fourth Amended Complaint with leave to amend. On September 11, 2015, Plaintiff filed a Fifth Amended Complaint. At March 31, 2016, the probable outcome of this litigation cannot be determined, nor can the Company estimate a range of potential loss. In accordance with authoritative guidance on the evaluation of loss contingencies, the Company has not recorded an accrual related to this litigation. Madsen Medical, Inc. Litigation On February 22, 2016, an unfavorable jury verdict was delivered against the Company in its litigation in the U.S. District Court for the Southern District of California against Madsen Medical, Inc. (“MMI”), a former sales agent. Specifically, the jury awarded MMI $7.5 million in lost profits for tortious interference, $14.0 million for unjust enrichment, $20.0 million in punitive damages, and approximately $0.3 million in damages for breach of contract. he trial court entered judgment in favor of MMI in the amount of $27.8 million, which amount excluded the $14.0 million disgorgement awarded by the jury. Both parties have filed post-trial motions and the Company intends to appeal the verdict and subsequent judgment. Notwithstanding, during pendency of any appeals, the Company has agreed to escrow funds necessary to secure the amount of the judgment and attorneys’ fees and costs. The Company is in the process of establishing an escrow, but to date, no such funds have been placed in escrow. Historically the Company had believed the likelihood of a loss in this case was remote given the underlying facts of the case, however, during the quarter the judgment entered caused the Company to reassess its position. The Company, based on its own assessment as well as that of outside counsel, believes that upon either post-trial motions or appeal the judgment will be vacated and have deemed it probable that is the outcome. Accordingly, at March 31, 2016, the Company believes that the outcome of the case does not constitute a probable nor an estimable loss associated with the litigation but rather a reasonably possible loss rather than a remote loss as historically contemplated. Therefore, the Company has not recorded a loss contingency but has assessed a reasonable range of potential loss, which would be from zero to the current amount entered as a judgment, in accordance with the accounting guidance required by ASC 450, Contingencies.

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2016
Regulatory Matter [Abstract]
Regulatory Matters	12. Regulatory Matters In 2013, the Company received a federal administrative subpoena from the Office of the Inspector General of the U.S. Department of Health and Human Services (“OIG”) in connection with an investigation into possible false or otherwise improper claims submitted to Medicare and Medicaid. The subpoena sought discovery of documents for the period January 2007 through April 2013. In July 2015, the Company entered into a definitive settlement agreement. Under the terms of the agreement, the Company paid $13.5 million plus fees and accrued interest of approximately $0.3 million to resolve this matter. The settlement was not an admission of liability or wrongdoing by the Company, and the Company was not required to enter into a corporate integrity agreement with the OIG as part of the settlement. In accordance with the authoritative guidance on the evaluation of loss contingencies, the Company recorded a $13.8 million litigation charge related to this matter, which was included in the Consolidated Statements of Operations and funded during the three months ended March 31, 2015. On August 31, 2015, the Company received a civil investigative demand (“CID”) issued by the DOJ pursuant to the federal False Claims Act. The CID requires the delivery of a wide range of documents and information related to an investigation by the DOJ concerning allegations that the Company assisted a physician group customer in submitting improper claims for reimbursement and made improper payments to the physician group in violation of the Anti-Kickback Statute. The Company is cooperating with the DOJ. No assurance can be given as to the timing or outcome of this investigation. At March 31, 2016, the probable outcome of this matter cannot be determined, nor can the Company estimate a range of potential loss. In accordance with authoritative guidance on the evaluation of loss contingencies, the Company has not recorded an accrual related to this matter.

Description of Business and B19

Description of Business and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	Description of Business NuVasive, Inc. (the “Company” or “NuVasive”) was incorporated in Delaware on July 21, 1997, and began commercializing its products in 2001. The Company’s principal product offering includes a minimally-disruptive surgical platform called Maximum Access Surgery, or MAS. The MAS platform combines three categories of solutions that collectively minimize soft tissue disruption during spine fusion surgery, provide maximum visualization and are designed to enable safe and reproducible outcomes for the surgeon and the patient. The platform includes our proprietary software-driven nerve detection and avoidance systems, NVM5, and Intraoperative Monitoring (“IOM”), services and support; MaXcess, an integrated split-blade retractor system; and a wide variety of specialized implants and biologics. The Company also recently launched Integrated Global Alignment (“iGA”), in which products and computer assisted technology under the MAS platform help achieve more precise spinal alignment. The individual components of the MAS platform, and many of the Company’s products, can also be used in open or traditional spine surgery. The Company continues to focus research and development efforts to expand its MAS product platform and advance the applications of its unique technology into procedurally-integrated surgical solutions. The Company dedicates significant resources toward training spine surgeons on its unique technology and products. The Company’s primary business model is to loan its MAS systems to surgeons and hospitals that purchase implants, biologics and disposables for use in individual procedures. In addition, for larger customers, the Company’s proprietary nerve monitoring systems, MaXcess and surgical instrument sets are placed with hospitals for an extended period at no up-front cost to them. The Company also offers a range of bone allograft in patented saline packaging, disposables and spine implants, which include its branded CoRoent ® On February 11, 2016 the Company acquired Ellipse Technologies, Inc. (“Ellipse Technologies”), which now operates as a wholly owned subsidiary under the renamed legal entity NuVasive Specialized Orthopedics, Inc. (“NSO”). NSO designs and sells expandable growing rod implant systems that can be non-invasively lengthened following implantation with precise, incremental adjustments via an external remote controller using magnetic technology called MAGnetic External Control, or MAGEC. The technology platform provides the basis of NSO’s core product offerings, including MAGEC-EOS, which allows for the minimally invasive treatment of early-onset and adolescent scoliosis, as well as PRECICE limb lengthening system, which allows for the correction of long bone limb length discrepancy, as well as enhanced bone healing in patients that have experienced traumatic injury. The Company intends to continue development on a wide variety of projects intended to broaden surgical applications for greater procedural integration of its MAS techniques and additional applications of the MAGEC technology. Such applications include tumor, trauma, and deformity, as well as increased fixation options and sagittal alignment products. The Company also expects to continue expanding its other product and services offerings as it executes on its strategy to offer customers an end-to-end, integrated procedural solution for spine surgery that distinguishes the Company from traditional spine implant companies.
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The accompanying Unaudited Consolidated Financial Statements include the accounts of the Company and its majority-owned or controlled subsidiaries, collectively referred to as either NuVasive or the Company. The Company translates the financial statements of its foreign subsidiaries using end-of-period exchange rates for assets and liabilities and average exchange rates during each reporting period for results of operations. When there is a portion of equity in an acquired subsidiary not attributable, directly or indirectly, to the respective parent entity, the Company records the fair value of the non-controlling interests at the acquisition date and classifies the amounts attributable to non-controlling interests separately in equity in the Company's consolidated financial statements. Any subsequent changes in a parent's ownership interest while the parent retains its controlling financial interest in its subsidiary are accounted for as equity transactions. All significant intercompany balances and transactions have been eliminated in consolidation. The accompanying Unaudited Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Pursuant to these rules and regulations, the Company has condensed or omitted certain information and footnote disclosures it normally includes in its annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Operating results for the three months ended March 31, 2016 are not necessarily indicative of the results that may be expected for any other interim period or for the full year. These Unaudited Consolidated Financial Statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2015 included in the Company’s Annual Report on Form 10-K filed with the SEC. In the opinion of management, the Unaudited Consolidated Financial Statements include all adjustments that are of a normal and recurring nature that are necessary for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The Company has reclassified historically presented product offerings revenue to conform to the current year presentation. The reclassification had no impact on previously reported results of operations or financial position
Change in Accounting Estimates	Change in Accounting Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.
Recently Adopted Accounting Standards	Recent Accounting Pronouncements Not Yet Adopted In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers In January 2016, the FASB issued Accounting Standards Update No. 2016-01, Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities In February 2016, the FASB issued new guidance related to leases that outlines a comprehensive lease accounting model and supersedes the current lease guidance. The new guidance requires lessees to recognize lease liabilities and corresponding right-of-use assets for all leases with lease terms of greater than 12 months. It also changes the definition of a lease and expands the disclosure requirements of lease arrangements. The new guidance must be adopted using the modified retrospective approach and will be effective for the Company starting in the first quarter of fiscal 2019. Early adoption is permitted. The Company is in the process of determining the effects the adoption will have on its consolidated financial statements as well as whether to adopt the new guidance early. In March 2016, the FASB issued Accounting Standards Update 2016-09, Improvements to Employee Share-Based Payment Accounting (“ASU 2016-09”), which amends ASC Topic 718, Compensation – Stock Compensation. ASU 2016-09 includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements. ASU 2016-09 is effective for public entities for annual reporting periods beginning after December 15, 2016, and interim periods within that reporting period. Early adoption is permitted in any interim or annual period, with any adjustments reflected as of the beginning of the fiscal year of adoption. The Company is evaluating the impact of this standard on its financial statements. Recently Adopted Accounting Standards In April 2014, the FASB issued ASU No. 2015-03 amended requirements that require debt issuance costs, related to a recognized debt liability, to be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, effective for the Company beginning January 1, 2016 applied retroactively for all consolidated balance sheets presented. The Company applied the amended presentation requirements in the first quarter 2016, which does not have a material impact on its financial statements. This change resulted in a reclassification from other assets to senior convertible notes on the Consolidated Balance Sheets presented. See Note 6 to the Unaudited Consolidated Financial Statements for revised presentation.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) includes unrealized gains or losses on the Company’s marketable securities and foreign currency translation adjustments. The cumulative translation adjustments included in accumulated other comprehensive income (loss) were a net cumulative loss of $9.1 million and $11.6 million at March 31, 2016 and December 31, 2015, respectively.
Business Transition Costs	The Company incurs costs related to integration and business transition activities which include severance, relocation, consulting, and other costs directly associated to such activities. During the three months ended March 31, 2016, the business transition costs were immaterial to the results of operations. During the three months ended March 31, 2015, the Company incurred $5.4 million of such costs, which included a $3.4 million charge associated with the resignation of the Company’s former Chief Executive Officer and Chairman of the Board, which occurred in the first quarter 2015. The $3.4 million charge includes certain severance and compensation-related charges, net of certain forfeitures of previously recognized equity-based compensation.
Product Shipment Costs	Product Shipment Costs Product shipment costs are included in sales, marketing and administrative expense in the accompanying Consolidated Statements of Operations were $6.2 million and $5.1 million for the three months ended March 31, 2016 and March 31, 2015, respectively. The majority of the Company’s shipping costs are related to the loan of instrument sets, which are not sold as part of the Company’s core sales offering. Amounts billed to customers for shipping and handling of products are reflected in revenues and are not significant for any period presented.
Restructuring Charges	Restructuring Charges During the three months ended March 31, 2015, the Company recognized incremental restructuring and associated impairment charges of $2.3 million associated with exiting its New Jersey location and termination of the respective lease. The Company previously exited a portion of the facility, in the first quarter of 2014, and this represents the exit from the entire facility. The restructuring and impairment charges mainly consist of the future rental payments through 2017, net of estimated future sublease income, and elimination of related leasehold improvements and deferred rent liabilities. These charges were recorded As of March 31, 2016, the total recorded liability associated with this early lease termination was $3.6 million compared to $4.1 million at December 31, 2015. The liability consists of future rental payments net of estimated sublease income through 2017. The current portion of the liability is recorded within accounts payable and accrued liabilities and the long-term portion is recorded within other long-term liabilities in the Consolidated Balance Sheets for the periods presented.
Litigation Liability Gain	Litigation Liability Gain During the three months ended March 31, 2015, the Company recorded a litigation liability gain of $42.6 million resulting primarily from the recognition of a $56.4 million gain stemming from a favorable appeal in Phase 1 of the Medtronic litigation, partially offset by a litigation loss of $13.8 million in connection with the OIG investigation. There were no material litigation gains or losses recorded during the three months ended March 31, 2016. See Note 11 and Note 12 to the Unaudited Consolidated Financial Statements for further discussion.

Net (Loss) Income Per Share (Ta

Net (Loss) Income Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Computation of basic and diluted income per share	The following table sets forth the computation of basic and diluted (loss) income per share attributable to the Company: Three Months Ended March 31, ( in thousands, except per share data 2016 2015 Numerator: Net (loss) income available to the Company $ (8,886 ) $ 31,560 Denominator for basic and diluted net (loss) income per share: Weighted average common shares outstanding for basic 49,617 47,989 Dilutive potential common stock outstanding: Stock options and employee stock purchase plan — 1,528 Restricted stock units — 1,308 Warrants — — Senior Convertible Notes — 891 Weighted average common shares outstanding for diluted 49,617 51,716 Basic net (loss) income per share attributable to the Company $ (0.18 ) $ 0.66 Diluted net (loss) income per share attributable to the Company $ (0.18 ) $ 0.61
Anti-dilutive common stock equivalents not included in calculation of net income per diluted share	The following weighted outstanding common stock equivalents were not included in the calculation of net (loss) income per diluted share because their effects were anti-dilutive: Three Months Ended March 31, ( in thousands 2016 2015 Stock options, employee stock purchase plan, and restricted stock units 3,647 22 Warrants 20,418 9,553 Senior Convertible Notes 19,336 - Total 43,401 9,575

Financial Instruments and Fai21

Financial Instruments and Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Composition of Marketable Securities	The composition of marketable securities is as follows: ( in thousands, except years Contractual Maturity (in years) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value March 31, 2016: Classified as current assets Corporate notes Less than 1 $ 18,622 $ 12 $ (4 ) $ 18,630 Commercial paper Less than 1 23,865 — — 23,865 Short-term marketable securities 42,487 12 (4 ) 42,495 Classified as non-current assets Securities of government-sponsored entities 1 to 2 10,590 11 — 10,601 Corporate notes 1 to 2 7,772 10 (2 ) 7,780 Long-term marketable securities 18,362 21 (2 ) 18,381 Total marketable securities at March 31, 2016 $ 60,849 $ 33 $ (6 ) $ 60,876 December 31, 2015: Classified as current assets Certificates of deposit Less than 1 $ 6,615 $ — $ — $ 6,615 Corporate notes Less than 1 108,739 5 (173 ) 108,571 Commercial paper Less than 1 21,991 — — 21,991 Securities of government-sponsored entities Less than 1 28,284 — (38 ) 28,246 Short-term marketable securities 165,629 5 (211 ) 165,423 Classified as non-current assets Certificates of deposit 1 to 2 12,392 — — 12,392 Corporate notes 1 to 2 43,857 — (109 ) 43,748 Securities of government-sponsored entities 1 to 2 56,412 — (220 ) 56,192 Long-term marketable securities 112,661 — (329 ) 112,332 Total marketable securities at December 31, 2015 $ 278,290 $ 5 $ (540 ) $ 277,755
Schedule of Derivatives Not Designated as Cash Flow Hedges	The following table summarizes the fair values of derivative instruments at March 31, 2016 and December 31, 2015: Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet March 31, December 31, Balance Sheet March 31, December 31, ( in thousands Location 2016 2015 Location 2016 2015 Derivative instruments not designated as cash flow hedges Forward exchange contracts Other current assets $ — * Other current liabilities $ 120 — Total derivatives $ — * $ 120 — *De minimis amount recognized in the hedge relationship.
Schedule of Derivative Instruments Effect on Statements of Operations	The following table summarizes the effect of derivative instruments on the Consolidated Statements of Operations for the three months ended March 31, 2016 and March 31, 2015: Three Months Ended Three Months Ended March 31, 2016 March 31, 2015 Location of Amount of Location of Amount of (Gain)/Loss (Gain)/Loss (Gain)/Loss (Gain)/Loss Recognized in Recognized in Recognized in Recognized in ( in thousands Income Income Income Income Derivative instruments not designated as cash flow hedges Forward exchange contracts Other (income) expense $ 179 Other (income) expense $ (2,165 ) Total derivatives $ 179 $ (2,165 )
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The fair values of the Company’s assets and liabilities, including cash equivalents, marketable securities, restricted investments, derivatives, and contingent consideration liabilities are measured at fair value on a recurring basis, and are determined under the fair value categories in accordance with the authoritative guidance as follows: Quoted Price in Significant Other Significant Active Market Observable Inputs Unobservable ( in thousands Total (Level 1) (Level 2) Inputs (Level 3) March 31, 2016: Money market funds $ 217,466 $ 217,466 $ — $ — Corporate notes 26,410 — 26,410 — Commercial paper 23,865 — 23,865 — Securities of government-sponsored entities 10,601 — 10,601 — Total assets $ 278,342 $ 217,466 $ 60,876 $ — December 31, 2015: Money market funds $ 68,425 $ 68,425 $ — $ — Certificates of deposit 19,007 19,007 — — Corporate notes 152,319 — 152,319 — Commercial paper 21,991 — 21,991 — Securities of government-sponsored entities 115,929 — 115,929 — Total assets $ 377,671 $ 87,432 $ 290,239 $ —
Fair Value Liabilities Measured on Recurring Basis Unobservable Input Reconciliation	The following table sets forth the changes in the estimated fair value of the Company’s liabilities measured on a recurring basis using significant unobservable inputs (Level 3): Three Months Ended March 31, ( in thousands 2016 2015 Fair value measurement at beginning of period $ — $ 644 Contingent consideration liability recorded upon acquisition 21,439 — Change in fair value measurement included in operating expenses — (36 ) Contingent consideration paid or settled — (608 ) Fair value measurement at end of period $ 21,439 $ —

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and intangible assets	Goodwill and intangible assets consisted of the following: Weighted- Average Amortization ( in thousands, except years Period Gross Accumulated Intangible March 31, 2016: (in years) Amount Amortization Assets, net Intangible assets subject to amortization: Developed technology 8 $ 226,548 $ (43,389 ) $ 183,159 Manufacturing know-how and trade secrets 12 21,817 (13,707 ) 8,110 Trade name and trademarks 9 25,700 (5,653 ) 20,047 Customer relationships 9 84,436 (29,663 ) 54,773 Total intangible assets subject to amortization 8 $ 358,501 $ (92,412 ) $ 266,089 Intangible assets not subject to amortization: Goodwill $ 404,307 Total goodwill and intangible assets, net $ 670,396 Weighted- Average Amortization Period Gross Accumulated Intangible December 31, 2015: (in years) Amount Amortization Assets, net Intangible assets subject to amortization: Developed technology 9 $ 92,648 $ (37,382 ) $ 55,266 Manufacturing know-how and trade secrets 12 21,787 (13,296 ) 8,491 Trade name and trademarks 11 9,500 (5,068 ) 4,432 Customer relationships 8 44,752 (27,865 ) 16,887 Total intangible assets subject to amortization 10 $ 168,687 $ (83,611 ) $ 85,076 Intangible assets not subject to amortization: Goodwill $ 154,281 Total goodwill and intangible assets, net $ 239,357
Schedule of changes in the carrying value of goodwill	The following table summarizes the changes in the carrying value of the Company’s goodwill: Three Months Ended March 31, ( in thousands 2016 2015 Goodwill at beginning of period $ 154,281 $ 154,443 Increases recorded in business combinations 249,973 — Changes resulting from foreign currency fluctuations 53 (170 ) Goodwill at end of period $ 404,307 $ 154,273
Future amortization expense related to intangible assets	Total future amortization expense related to intangible assets subject to amortization at March 31, 2016 is set forth in the table below: ( in thousands Remaining 2016 $ 33,232 2017 41,114 2018 39,228 2019 37,749 2020 37,338 2021 35,477 Thereafter through 2027 41,951 Total future amortization expense $ 266,089

Business Combinations (Tables)

Business Combinations (Tables)	3 Months Ended
	Mar. 31, 2016
Business Acquisition [Line Items]
Summary of assets and liabilities included in the accompanying consolidated balance sheets	Total assets and liabilities of Progentix included in the accompanying Consolidated Balance Sheets are as follows: ( in thousands March 31, 2016 December 31, 2015 Total current assets $ 358 $ 353 Identifiable intangible assets, net 12,511 13,048 Goodwill 12,654 12,654 Accounts payable and accrued expenses 714 574 Deferred tax liabilities, net 1,304 1,496 Non-controlling interests 6,852 7,309
Reconciliation of equity (net assets) attributable to the non-controlling interests	The following is a reconciliation of equity (net assets) attributable to the non-controlling interests: Three Months Ended March 31, ( in thousands 2016 2015 Non-controlling interests at beginning of period $ 7,309 $ 8,310 Less: Net loss attributable to the non-controlling interests 457 163 Non-controlling interests at end of period $ 6,852 $ 8,147
Ellipse Technologies Inc [Member]
Business Acquisition [Line Items]
Schedule of allocation for purchase price to the assets acquired and liabilities assumed based on fair values	The Company is still in the process of finalizing the purchase price allocation given the timing of the acquisition and the size and scope of the assets and liabilities subject to valuation. While the Company does not expect material changes in the valuation outcome, certain assumptions and findings that were in place at the date of acquisition could result in changes in the purchase price allocation. The allocation of the purchase price to the assets acquired and liabilities assumed based on their fair values was as follows: ( in thousands Cash paid for purchase $ 382,174 Accounts receivable 7,148 Inventory 22,451 Other current assets 1,855 Property, plant and equipment, net 6,725 Definite-lived intangible assets: Developed technology 133,900 Customer relationships 33,200 Trade names 16,200 Goodwill 242,675 Deferred tax assets 17,694 Other assets 1,868 Contingent consideration liability 18,800 Deferred tax liabilities 75,999 Other liabilities assumed 6,743 $ 382,174
Schedule of unaudited pro forma financial information	The following table presents the unaudited pro forma results for the three months ended March 31, 2016 and March 31, 2015. The unaudited pro forma financial information combines the results of operations of NuVasive and Ellipse Technologies as though the companies had been combined as of January 1, 2015, and the pro forma information is presented for informational purposes only and is not indicative of the results of operations that would have been achieved if the acquisition had taken place at such times. The unaudited pro forma results presented include non-recurring adjustments directly attributable to the business combination, including $6.5 million in amortization charges for acquired intangible assets, a $7.4 million adjustment for increased fair value of acquired inventory, $0.1 million reduction to revenue for deferred revenue adjustments, $4.0 million in acquisition related expenses, Three Months Ended March 31, ( in thousands, except per share amounts 2016 2015 Revenues $ 221,012 $ 200,636 Net (loss) income attributable to NuVasive, Inc. (6,013 ) 18,140 Net (loss) income per share attributable to NuVasive, Inc.: Basic $ (0.12 ) $ 0.38 Diluted $ (0.12 ) $ 0.35

Indebtedness (Tables)

Indebtedness (Tables)	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Net carrying amount of the debt component	The carrying values of the Company’s Senior Convertible Notes are as follows: ( in thousands March 31, 2016 December 31, 2015 2.75% Senior Convertible Notes due 2017: Principal amount $ 125,732 $ 402,500 Unamortized debt discount (6,818 ) (25,958 ) Unamortized debt issuance costs (957 ) (3,622 ) 117,957 372,920 2.25% Senior Convertible Notes due 2021: Principal amount 650,000 — Unamortized debt discount (84,144 ) — Unamortized debt issuance costs (14,415 ) — 551,441 — Total Senior Convertible Notes $ 669,398 $ 372,920

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Compensation costs included in statement of income for all stock-based compensation arrangements	The compensation cost that has been included in the Consolidated Statements of Operations for all stock-based compensation arrangements was as follows: Three Months Ended March 31, ( in thousands 2016 2015 Sales, marketing and administrative expense $ 4,430 $ 7,277 Research and development expense 10 259 Cost of goods sold 52 75 Stock-based compensation expense before taxes 4,492 7,611 Related income tax benefits (1,797 ) (3,044 ) Stock-based compensation expense, net of taxes $ 2,695 $ 4,567
Weighted average assumptions used to estimate fair value of stock options granted and stock purchase rights under ESPP	The weighted average assumptions used to estimate the fair value of stock purchase rights under the employee stock purchase plan (“ESPP”) are as follows: Three Months Ended March 31, 2016 2015 ESPP Volatility 31 % 44 % Expected term (years) 0.6 1.4 Risk free interest rate 0.3 % 0.2 % Expected dividend yield — % — %

Business Segment, Product and G

Business Segment, Product and Geographical Information (Tables)	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Revenue from External Customers by Products and Services	Three Months Ended March 31, ( in thousands 2016 2015 Spinal Hardware $ 151,957 $ 131,222 Surgical Support 63,147 61,161 Total Revenue $ 215,104 $ 192,383
Schedule of Revenue from Net Property and Equipment by Geographical Areas	Revenue and property and equipment, net, by geographic area were as follows: Revenue Property and Equipment, Net Three Months Ended March 31, March 31, December 31, ( in thousands 2016 2015 2016 2015 United States $ 188,351 $ 169,926 $ 124,229 $ 113,037 International (excludes Puerto Rico) 26,753 22,457 28,759 28,404 Total $ 215,104 $ 192,383 $ 152,988 $ 141,441

Description of Business and B27

Description of Business and Basis of Presentation (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Schedule Of Description Of Business And Basis Of Presentation [Line Items]
Translation Adjustment Functional to Reporting Currency, Net of Tax	$ (9,100,000)		$ (11,600,000)
Relocation, consulting, and other costs	0	$ 5,400,000
Severance Costs		3,400,000
Product shipment costs	6,200,000	5,100,000
Total recorded liability associated with early lease termination	3,600,000		$ 4,100,000
Litigation accrual adjustment	$ 0	42,575,000
OIG [Member]
Schedule Of Description Of Business And Basis Of Presentation [Line Items]
Litigation accrual adjustment		13,800,000
Litigation loss offset		13,800,000
Medtronic Litigation [Member]
Schedule Of Description Of Business And Basis Of Presentation [Line Items]
Litigation accrual adjustment		56,400,000
Sales, Marketing and Administrative Expense [Member]
Schedule Of Description Of Business And Basis Of Presentation [Line Items]
Restructuring and associated impairment charges		2,300,000
Chief Executive Officer and Chairman of the Board [Member]
Schedule Of Description Of Business And Basis Of Presentation [Line Items]
Severance Costs		$ 3,400,000

Net (Loss) Income Per Share - C

Net (Loss) Income Per Share - Computation of Basic and Diluted Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Numerator:
Net (loss) income available to the Company	$ (8,886)	$ 31,560
Denominator for basic and diluted net (loss) income per share:
Weighted average common shares outstanding for basic	49,617	47,989
Dilutive potential common stock outstanding:
Weighted average common shares outstanding for diluted	49,617	51,716
Basic net (loss) income per share attributable to the Company	$ (0.18)	$ 0.66
Diluted net (loss) income per share attributable to the Company	$ (0.18)	$ 0.61
Stock Options and Employee Stock Purchase Plan [Member]
Dilutive potential common stock outstanding:
Incremental common shares attributable to dilutive effect of share-based payment arrangements		1,528
Restricted Stock Units [Member]
Dilutive potential common stock outstanding:
Incremental common shares attributable to dilutive effect of share-based payment arrangements		1,308
Senior Convertible Notes [Member]
Dilutive potential common stock outstanding:
Incremental common shares attributable to dilutive effect of share-based payment arrangements		891

Net (Loss) Income Per Share - A

Net (Loss) Income Per Share - Anti-dilutive Common Stock Equivalents Not Included in Calculation of Net Income Per Diluted Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	43,401	9,575
Stock Options, Employee Stock Purchase Plan, and Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	3,647	22
Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	20,418	9,553
Senior Convertible Notes [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	19,336

Financial Instruments and Fai30

Financial Instruments and Fair Value Measurements - Composition of Marketable Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	$ 60,849	$ 278,290
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	33	5
Available-for-sale Securities, Gross Unrealized Losses, Before Tax	(6)	(540)
Available-for-sale Securities, Fair Value	60,876	277,755
Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	42,487	165,629
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	12	5
Available-for-sale Securities, Gross Unrealized Losses, Before Tax	(4)	(211)
Available-for-sale Securities, Fair Value	42,495	165,423
Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	18,362	112,661
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	21
Available-for-sale Securities, Gross Unrealized Losses, Before Tax	(2)	(329)
Available-for-sale Securities, Fair Value	18,381	112,332
Commercial paper [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	23,865	21,991
Available-for-sale Securities, Fair Value	$ 23,865	$ 21,991
Commercial paper [Member] | Maximum [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	1 year	1 year
Certificates of deposit [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost		$ 6,615
Available-for-sale Securities, Fair Value		6,615
Certificates of deposit [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost		12,392
Available-for-sale Securities, Fair Value		$ 12,392
Certificates of deposit [Member] | Maximum [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity		1 year
Certificates of deposit [Member] | Maximum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity		2 years
Certificates of deposit [Member] | Minimum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity		1 year
Corporate notes [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	$ 18,622	$ 108,739
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	12	5
Available-for-sale Securities, Gross Unrealized Losses, Before Tax	(4)	(173)
Available-for-sale Securities, Fair Value	18,630	108,571
Corporate notes [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	7,772	43,857
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	10
Available-for-sale Securities, Gross Unrealized Losses, Before Tax	(2)	(109)
Available-for-sale Securities, Fair Value	$ 7,780	$ 43,748
Corporate notes [Member] | Maximum [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	1 year	1 year
Corporate notes [Member] | Maximum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	2 years	2 years
Corporate notes [Member] | Minimum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	1 year	1 year
Securities of government-sponsored entities [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost		$ 28,284
Available-for-sale Securities, Gross Unrealized Losses, Before Tax		(38)
Available-for-sale Securities, Fair Value		28,246
Securities of government-sponsored entities [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Cost	$ 10,590	56,412
Available-for-sale Securities, Gross Unrealized Gains, Before Tax	11
Available-for-sale Securities, Gross Unrealized Losses, Before Tax		(220)
Available-for-sale Securities, Fair Value	$ 10,601	$ 56,192
Securities of government-sponsored entities [Member] | Maximum [Member] | Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity		1 year
Securities of government-sponsored entities [Member] | Maximum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	2 years	2 years
Securities of government-sponsored entities [Member] | Minimum [Member] | Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities Contractual Maturity	1 year	1 year

Financial Instruments and Fai31

Financial Instruments and Fair Value Measurements (Details Textual)	3 Months Ended
	Mar. 31, 2016USD ($)investment	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Business Acquisition [Line Items]
Impairment charges recorded for earnings	$ 0
Unrealized loss position investment | investment	0
Net foreign currency exchange gains (losses), includes gains and losses from derivatives instruments	$ 100,000	$ 300,000
Contingent Consideration Liability [Member]
Business Acquisition [Line Items]
Contingent consideration liability recorded upon acquisition	21,439,000
Quoted price in active market (Level 1) [Member] | Convertible Notes due 2017 [Member]
Business Acquisition [Line Items]
Debt instrument, fair value disclosure	159,200,000		$ 551,400,000
Quoted price in active market (Level 1) [Member] | Senior Convertible Notes due 2021 [Member]
Business Acquisition [Line Items]
Debt instrument, fair value disclosure	696,700,000
Foreign Exchange Forward [Member]
Business Acquisition [Line Items]
Notional principal amount	$ 10,200,000	$ 8,500,000

Financial Instruments and Fai32

Financial Instruments and Fair Value Measurements - Schedule of Derivatives Not Designated as Cash Flow Hedges (Details) - Cash Flow Hedges [Member] - Not Designated As Hedging Instrument [Member] - Other Current Liabilities [Member] $ in Thousands	Mar. 31, 2016USD ($)
Derivative [Line Items]
Liability Derivatives	$ 120
Foreign Exchange Forward [Member]
Derivative [Line Items]
Liability Derivatives	$ 120

Financial Instruments and Fai33

Financial Instruments and Fair Value Measurements - Schedule of Derivative Instruments Effect on Statements of Operations (Details) - Cash Flow Hedges [Member] - Not Designated As Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Derivative Instruments Gain Loss [Line Items]
Amount of (Gain)/Loss Recognized in Income	$ 179	$ (2,165)
Foreign Exchange Forward [Member] | Other (Income) Expense [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of (Gain)/Loss Recognized in Income	$ 179	$ (2,165)

Financial Instruments and Fai34

Financial Instruments and Fair Value Measurements - Fair Value of Assets and Liabilities (Details) - Fair value measurements on recurring basis [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	$ 278,342	$ 377,671
Money Market Funds [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	217,466	68,425
Corporate notes [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	26,410	152,319
Commercial paper [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	23,865	21,991
Securities of government-sponsored entities [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	10,601	115,929
Certificates of deposit [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments		19,007
Quoted price in active market (Level 1) [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	217,466	87,432
Quoted price in active market (Level 1) [Member] | Money Market Funds [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	217,466	68,425
Quoted price in active market (Level 1) [Member] | Certificates of deposit [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments		19,007
Significant other observable inputs (Level 2) [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	60,876	290,239
Significant other observable inputs (Level 2) [Member] | Corporate notes [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	26,410	152,319
Significant other observable inputs (Level 2) [Member] | Commercial paper [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	23,865	21,991
Significant other observable inputs (Level 2) [Member] | Securities of government-sponsored entities [Member]
Marketable Securities and Restricted Investments
Total marketable securities and restricted investments	$ 10,601	$ 115,929

Financial Instruments and Fai35

Financial Instruments and Fair Value Measurements - Estimated Fair Value of Liabilities Measured on a Recurring Basis Using Significant Unobservable Inputs (Level 3) (Details) - Contingent Consideration Liability [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value measurement at beginning of period		$ 644
Contingent consideration liability recorded upon acquisition	$ 21,439
Change in fair value measurement included in operating expenses		(36)
Contingent consideration paid or settled		$ (608)
Fair value measurement at end of period	$ 21,439

Goodwill and Intangible Asset36

Goodwill and Intangible Assets (Details 1) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Intangible assets subject to amortization:
Weighted Average Amortization Period	8 years	10 years
Gross Amount	$ 358,501	$ 168,687
Accumulated Amortization	(92,412)	(83,611)
Intangible Assets, net	266,089	85,076
Intangible assets not subject to amortization:
Goodwill	404,307	154,281	$ 154,273	$ 154,443
Total goodwill and intangible assets, net	$ 670,396	$ 239,357
Developed technology [Member]
Intangible assets subject to amortization:
Weighted Average Amortization Period	8 years	9 years
Gross Amount	$ 226,548	$ 92,648
Accumulated Amortization	(43,389)	(37,382)
Intangible Assets, net	$ 183,159	$ 55,266
Manufacturing know-how and trade secrets [Member]
Intangible assets subject to amortization:
Weighted Average Amortization Period	12 years	12 years
Gross Amount	$ 21,817	$ 21,787
Accumulated Amortization	(13,707)	(13,296)
Intangible Assets, net	$ 8,110	$ 8,491
Trade name and trademarks [Member]
Intangible assets subject to amortization:
Weighted Average Amortization Period	9 years	11 years
Gross Amount	$ 25,700	$ 9,500
Accumulated Amortization	(5,653)	(5,068)
Intangible Assets, net	$ 20,047	$ 4,432
Customer relationships [Member]
Intangible assets subject to amortization:
Weighted Average Amortization Period	9 years	8 years
Gross Amount	$ 84,436	$ 44,752
Accumulated Amortization	(29,663)	(27,865)
Intangible Assets, net	$ 54,773	$ 16,887

Goodwill and Intangible Asset37

Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Definite-lived intangible assets	$ 189,800
Goodwill	249,973
Amortization expense related to intangible assets	$ 8,800	$ 3,900

Goodwill and Intangible Asset38

Goodwill and Intangible Assets (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill at beginning of period	$ 154,281	$ 154,443
Increases recorded in business combinations	249,973
Changes resulting from foreign currency fluctuations	53	(170)
Goodwill at end of period	$ 404,307	$ 154,273

Goodwill and Intangible Asset39

Goodwill and Intangible Assets (Details 3) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Future amortization expense related to intangible assets
Remaining 2,016	$ 33,232
2,017	41,114
2,018	39,228
2,019	37,749
2,020	37,338
2,021	35,477
Thereafter through 2027	41,951
Intangible Assets, net	$ 266,089	$ 85,076

Business Combinations (Details

Business Combinations (Details Textual) - USD ($)	Feb. 11, 2016	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2009
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		8 years		10 years
Amortization expense related to intangible assets		$ 8,800,000	$ 3,900,000
Technology-Based Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		8 years		9 years
Customer-Related Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		9 years		8 years
Ellipse Technologies Inc [Member]
Business Acquisition [Line Items]
Business acquisition. date of acquisition		Feb. 11, 2016
Business acquisition, purchase price	$ 380,000,000
Business combination, holdback service period	6 months
Business acquisition, potential future milestone payment	$ 30,000,000
Cash payment on purchase of outstanding shares	382,174,000
Contingent liability	$ 18,800,000
Revenue from operation of NSO		$ 5,800,000
Loss from operation of NSO		(1,600,000)
Ellipse Technologies Inc [Member] | Amortization Charges [Member]
Business Acquisition [Line Items]
Amortization expense related to intangible assets		6,500,000
Ellipse Technologies Inc [Member] | Fair Value Adjustment To Inventory [Member]
Business Acquisition [Line Items]
Fair value adjustment of acquired inventory		7,400,000
Ellipse Technologies Inc [Member] | Acquisition Related Costs [Member]
Business Acquisition [Line Items]
Acquisition costs related to merger		4,000,000
Ellipse Technologies Inc [Member] | Deferred Revenue Adjustments [Member]
Business Acquisition [Line Items]
Deferred revenue adjustments and related tax effects		(100,000)
Ellipse Technologies Inc [Member] | Selling, Marketing and Administrative Expenses [Member]
Business Acquisition [Line Items]
Acquisition costs related to merger		$ 4,000,000
Ellipse Technologies Inc [Member] | Technology-Based Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		7 years
Ellipse Technologies Inc [Member] | Customer-Related Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		9 years
Ellipse Technologies Inc [Member] | Trade Name Related Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets, weighted-average useful life		7 years
Progentix Orthobiology [Member]
Business Acquisition [Line Items]
Advanced loan accordance to loan agreement		$ 5,300,000
Accrued interest rate of loan		6.00%
Progentix Orthobiology [Member] | Preferred Stock Purchase Agreement [Member]
Business Acquisition [Line Items]
Cash payment on purchase of outstanding shares					$ 10,000,000
Percentage of ownership Interests acquired					40.00%

Business Combinations (Details)

Business Combinations (Details) - USD ($) $ in Thousands	Feb. 11, 2016	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Definite-lived intangible assets:
Goodwill		$ 404,307	$ 154,281	$ 154,273	$ 154,443
Ellipse Technologies Inc [Member]
Business Acquisition [Line Items]
Cash paid for purchase	$ 382,174
Accounts receivable	7,148
Inventory	22,451
Other current assets	1,855
Property, plant and equipment, net	6,725
Definite-lived intangible assets:
Goodwill	242,675
Deferred tax assets	17,694
Other assets	1,868
Contingent consideration liability	18,800
Deferred tax liabilities	75,999
Other liabilities assumed	6,743
Total purchase price of assets acquired and liabilities assumed, net	382,174
Ellipse Technologies Inc [Member] | Developed technology [Member]
Definite-lived intangible assets:
Definite-lived intangible assets	133,900
Ellipse Technologies Inc [Member] | Customer relationships [Member]
Definite-lived intangible assets:
Definite-lived intangible assets	33,200
Ellipse Technologies Inc [Member] | Trade Names [Member]
Definite-lived intangible assets:
Definite-lived intangible assets	$ 16,200

Business Combinations (Detail42

Business Combinations (Details 1) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Business Combinations [Abstract]
Revenues	$ 221,012	$ 200,636
Net (loss) income attributable to NuVasive, Inc.	$ (6,013)	$ 18,140
Net (loss) income per share attributable to NuVasive, Inc.:
Basic	$ (0.12)	$ 0.38
Diluted	$ (0.12)	$ 0.35

Business Combinations (Detail43

Business Combinations (Details 2) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Total current assets	$ 692,164	$ 702,827
Identifiable intangible assets, net	266,089	85,076
Goodwill	404,307	154,281	$ 154,273	$ 154,443
Non-controlling interests	6,852	7,309
Variable Interest Entity [Member]
Business Acquisition [Line Items]
Non-controlling interests	6,852	7,309	$ 8,147	$ 8,310
Variable Interest Entity [Member] | Progentix Orthobiology [Member]
Business Acquisition [Line Items]
Total current assets	358	353
Identifiable intangible assets, net	12,511	13,048
Goodwill	12,654	12,654
Accounts payable and accrued expenses	714	574
Deferred tax liabilities, net	1,304	1,496
Non-controlling interests	$ 6,852	$ 7,309

Reconciliation of Equity (Net A

Reconciliation of Equity (Net Assets) Attributable to the Non-controlling Interests (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Reconciliation of equity (net assets) attributable to the non-controlling interests
Non-controlling interests at beginning of period	$ 7,309
Non-controlling interests at end of period	6,852
Variable Interest Entity [Member]
Reconciliation of equity (net assets) attributable to the non-controlling interests
Non-controlling interests at beginning of period	7,309	$ 8,310
Less: Net loss attributable to the non-controlling interests	457	163
Non-controlling interests at end of period	$ 6,852	$ 8,147

Indebtedness (Details)

Indebtedness (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2011	Jun. 30, 2011
Debt Instrument [Line Items]
Total Senior Convertible Notes	$ 669,398	$ 372,920
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member]
Debt Instrument [Line Items]
Principal amount	125,732	402,500		$ 402,500
Unamortized debt discount	(6,818)	(25,958)	$ (88,900)
Unamortized debt issuance costs	(957)	(3,622)
Total Senior Convertible Notes	117,957	$ 372,920
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member]
Debt Instrument [Line Items]
Principal amount	650,000
Unamortized debt discount	(84,144)
Unamortized debt issuance costs	(14,415)
Total Senior Convertible Notes	$ 551,441

Indebtedness (Parenthetical) (D

Indebtedness (Parenthetical) (Details)	Mar. 31, 2016	Dec. 31, 2015	Jun. 30, 2011
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes	2.75%	2.75%	2.75%
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes	2.25%	2.25%

Indebtedness (Details Textual)

Indebtedness (Details Textual)	Feb. 11, 2016USD ($)	Mar. 31, 2016USD ($)$ / sharesshares	Jun. 30, 2011USD ($)$ / shares	Mar. 31, 2016USD ($)$ / sharesshares	Mar. 31, 2015USD ($)	Dec. 31, 2011USD ($)$ / sharesshares	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of convertible debt, net of issuance costs				$ 634,140,000
Contractual coupon interest expense				2,500,000	$ 2,800,000
Amortization of debt discount (premium)				3,700,000	3,800,000
Amortization of debt issuance costs				500,000	$ 500,000
Derivative, maturity date						Jul. 1, 2017
Proceeds from sale of warrants				44,850,000		$ 47,900,000
Warrant strike price | $ / shares						$ 988.51
Number of common stock shares preferred stock convertible into | shares						20
Loss on repurchases of convertible notes				(17,444,000)
Revolving Senior Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 150,000,000
Credit facility, expiration date	2021-02
Revolving loan outstanding		$ 0		$ 0
Letters of Credit [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 15,000,000
Swing Line Loans [Member]
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity	$ 5,000,000
2021 Warrants [Member]
Debt Instrument [Line Items]
Proceeds from sale of warrants		$ 44,900,000
Warrant strike price | $ / shares		$ 80		$ 80
2021 Hedge [Member]
Debt Instrument [Line Items]
Number of common stock to be purchased | shares		10,865,270
Derivative, maturity date		Mar. 15, 2021
2017 Hedge [Member]
Debt Instrument [Line Items]
Number of common stock to be purchased | shares						9,553,096
Cost of hedge transaction						$ 80,100,000
2017 Hedge [Member] | Other Expense [Member]
Debt Instrument [Line Items]
Embedded derivative, gain (loss) reclassified to earnings						$ 37,100,000
Minimum [Member]
Debt Instrument [Line Items]
Class of warrant or rights expiry month and year						2017-09
Minimum [Member] | Revolving Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.20%
Minimum [Member] | Revolving Senior Credit Facility [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Credit facility bear interest rate	1.00%
Minimum [Member] | Revolving Senior Credit Facility [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Credit facility bear interest rate	0.00%
Minimum [Member] | 2021 Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or rights expiry month and year		2021-06
Maximum [Member]
Debt Instrument [Line Items]
Class of warrant or rights expiry month and year						2018-01
Maximum [Member] | Revolving Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.40%
Maximum [Member] | Revolving Senior Credit Facility [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Credit facility bear interest rate	2.00%
Maximum [Member] | Revolving Senior Credit Facility [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Credit facility bear interest rate	1.25%
Maximum [Member] | Series A Convertible Participating Preferred Stock [Member]
Debt Instrument [Line Items]
Number of preferred or common stock into which the warrants is converted | shares						477,654
Maximum [Member] | 2021 Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or rights expiry month and year		2021-12
Additional Paid-in Capital [Member] | 2021 Hedge [Member]
Debt Instrument [Line Items]
Cost of hedge transaction		$ 111,200,000		$ 111,200,000
Additional Paid-in Capital [Member] | 2017 Hedge [Member]
Debt Instrument [Line Items]
Embedded derivative, amount reclassified to stockholders' equity						$ 43,000,000
Common Shares [Member] | Maximum [Member]
Debt Instrument [Line Items]
Number of preferred or common stock into which the warrants is converted | shares						9,553,080
Common Shares [Member] | Maximum [Member] | 2021 Warrants [Member]
Debt Instrument [Line Items]
Number of preferred or common stock into which the warrants is converted | shares		10,865,270		10,865,270
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member]
Debt Instrument [Line Items]
Principal amount		$ 650,000,000		$ 650,000,000
Proceeds from issuance of convertible debt, net of issuance costs		$ 634,100,000
Interest rate on convertible notes		2.25%		2.25%			2.25%
Debt instrument, maturity date		Mar. 15, 2021
Initial conversion rate adjustment, shares		16.7158
Principal amount of debt considered for conversion rate		$ 1,000
Initial conversion price of convertible notes | $ / shares		$ 59.82		$ 59.82
Contractual coupon interest expense				$ 600,000
Amortization of debt discount (premium)				600,000
Amortization of debt issuance costs				$ 100,000
Effective interest rate		5.80%		5.80%
Debt redemption price percentage		100.00%
Principal payments due		$ 0		$ 0
Fair value of debt conversion cost		84,144,000		84,144,000
Net proceeds of unsecured senior convertible notes		345,200,000
Unamortized debt issuance costs		$ 14,415,000		14,415,000
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Scenario Two [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion		5 days
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of conversion price		130.00%
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Minimum [Member] | Scenario One [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion		20 days
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Percentage of conversion price		98.00%
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Maximum [Member] | Scenario One [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion		30 days
2.25% Senior Convertible Notes [Member] | Convertible Notes due 2021 [Member] | Additional Paid-in Capital [Member]
Debt Instrument [Line Items]
Embedded derivative, amount reclassified to stockholders' equity				84,800,000
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member]
Debt Instrument [Line Items]
Principal amount		$ 125,732,000	$ 402,500,000	$ 125,732,000			$ 402,500,000
Proceeds from issuance of convertible debt, net of issuance costs			$ 359,200,000
Interest rate on convertible notes		2.75%	2.75%	2.75%			2.75%
Debt instrument, maturity date			Jul. 1, 2017
Initial conversion rate adjustment, shares			23.7344
Principal amount of debt considered for conversion rate			$ 1,000
Initial conversion price of convertible notes | $ / shares			$ 42.13
Effective interest rate						8.00%
Fair value of debt conversion cost		$ 6,818,000		$ 6,818,000		$ 88,900,000	$ 25,958,000
Principal amount of debt instruments offering to repurchase		276,800,000		276,800,000
Unamortized debt issuance costs		$ 957,000		957,000			$ 3,622,000
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Other Income [Member]
Debt Instrument [Line Items]
Embedded derivative, gain (loss) reclassified to earnings						$ 39,500,000
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Other Expense [Member]
Debt Instrument [Line Items]
Loss on repurchases of convertible notes				$ (17,400,000)
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Scenario Two [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion						5 days
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of conversion price						130.00%
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Minimum [Member] | Scenario One [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion						20 days
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Percentage of conversion price						98.00%
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Maximum [Member] | Scenario One [Member]
Debt Instrument [Line Items]
Consecutive trading days considered for debt conversion						30 days
2.75% Senior Convertible Notes [Member] | Convertible Notes due 2017 [Member] | Additional Paid-in Capital [Member]
Debt Instrument [Line Items]
Embedded derivative, amount reclassified to stockholders' equity						$ 49,400,000

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 4,492	$ 7,611
Related income tax benefits	(1,797)	(3,044)
Stock-based compensation expense, net of taxes	2,695	4,567
Sales, Marketing and Administrative Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	4,430	7,277
Research and development expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	10	259
Cost of goods sold [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 52	$ 75

Stock-Based Compensation (Detai

Stock-Based Compensation (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	0	0
Number of common stock issued to exercise stock options	100,000		3,300,000
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
ESPP offering period	2 years
ESPP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of issuance price of stock under the stock issuance program	85.00%
Maximum percentage of annual compensation	15.00%
Maximum amount withheld to purchase shares of the company	$ 21,250
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unamortized cost related to share-based compensation	$ 56,100,000
Number of shares of common stock issued upon vesting of RSUs	700,000		1,400,000
Performance Based Restricted Stock Units (PRSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average contractual term	2 years 8 months 12 days

Stock-Based Compensation, Assum

Stock-Based Compensation, Assumptions Table (Details) - ESPP [Member]	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Weighted average assumptions used to estimate fair value of stock options granted and stock purchase rights under ESPP
Volatility	31.00%	44.00%
Expected term (years)	7 months 6 days	1 year 4 months 24 days
Risk free interest rate	0.30%	0.20%

Income Taxes (Details Textual)

Income Taxes (Details Textual) $ in Millions	3 Months Ended
	Mar. 31, 2016USD ($)
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent	30.00%
Increase in gross unrecognized tax benefits	$ 1.5

Business Segment, Product and52

Business Segment, Product and Geographic Information (Details Textual)	3 Months Ended
	Mar. 31, 2016segment
Segment Reporting [Abstract]
Number of operating segments	1

Business Segment, Product and53

Business Segment, Product and Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Entity Wide Information Revenue From External Customer [Line Items]
Total Revenue	$ 215,104	$ 192,383
Spinal Hardware [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Total Revenue	151,957	131,222
Surgical Support [Member]
Entity Wide Information Revenue From External Customer [Line Items]
Total Revenue	$ 63,147	$ 61,161

Business Segment, Product and54

Business Segment, Product and Geographic Information (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Revenues and Net Property and Equipment by Geographical Areas [Line Items]
Revenue	$ 215,104	$ 192,383
Property and Equipment, Net	152,988		$ 141,441
UNITED STATES
Revenues and Net Property and Equipment by Geographical Areas [Line Items]
Revenue	188,351	169,926
Property and Equipment, Net	124,229		113,037
International [Member]
Revenues and Net Property and Equipment by Geographical Areas [Line Items]
Revenue	26,753	$ 22,457
Property and Equipment, Net	$ 28,759		$ 28,404

Commitments (Details Textual)

Commitments (Details Textual) $ in Millions	3 Months Ended
	Mar. 31, 2016USD ($)
Commitments (Textual) [Abstract]
Restricted cash for security deposit	$ 1.5
Total minimum future lease payments	7.5
Licensing and Purchasing Agreements [Member]
Commitments (Textual) [Abstract]
Obligation under consultancy arrangements	$ 23.4
Revenue based milestone period	achieved prior to 2024
Executive Severance Plans [Member]
Commitments (Textual) [Abstract]
Other commitments, future minimum payments, remainder of fiscal year	$ 22.3

Contingencies (Details)

Contingencies (Details)

Mar. 18, 2016USD ($)

Feb. 22, 2016USD ($)

Jul. 20, 2015USD ($)

Dec. 02, 2014USD ($)

Apr. 25, 2013USD ($)

Sep. 20, 2011USD ($)patent

Jul. 31, 2015USD ($)

Oct. 31, 2010USD ($)

Aug. 31, 2008patent

Mar. 31, 2016USD ($)patent

Jun. 30, 2015USD ($)

Mar. 31, 2015USD ($)

Sep. 30, 2015USD ($)

Mar. 02, 2015USD ($)

Dec. 31, 2011USD ($)

Loss Contingencies [Line Items]

Litigation accrual adjustment

$ 0

$ 42,575,000

Loss contingency, estimate of possible loss

$ 87,600,000

Unrecorded royalty damages

$ 0

OIG [Member]

Loss Contingencies [Line Items]

Litigation accrual adjustment

13,800,000

Litigation loss offset

13,800,000

Loss contingency, settlement agreement, consideration

$ 13,500,000

Medtronic Litigation [Member]

Loss Contingencies [Line Items]

Litigation accrual adjustment

$ 56,400,000

Number of patents assigned or licensed | patent

12

9

Number of patents withdrawn | patent

3

Number of patents selected for litigation | patent

3

Company's patents in initial phase of litigation | patent

1

Litigation, damages awarded

$ 101,200,000

Loss contingency, settlement agreement, court

On May 15, 2013, the District Court granted the parties’ joint motion to dismiss claims relating to one of the three Medtronic patents pursuant to a settlement agreement, leaving two Medtronic patents remaining in the litigation. On June 11, 2013, the District Court granted the parties ongoing royalties with respect to the two Medtronic patents and the one Company patent remaining in the first phase of the case (the “June 2013 ruling”).

Company's cash and investment in escrow

$ 113,300,000

Release of funds from escrow

$ 114,100,000

Litigation liability

$ 101,200,000

Royalty accrual charge

7,900,000

Unrecorded royalty damages

700,000

Loss contingency, settlement agreement, consideration

$ 7,500,000

Trademark Infringement [Member]

Loss Contingencies [Line Items]

Litigation accrual adjustment

$ 2,800,000

Company's cash and investment in escrow

$ 32,500,000

Litigation liability

60,000,000

Loss contingency, settlement agreement, consideration

$ 27,200,000

Jury award

$ 60,000,000

Remaining litigation liability

0

Restricted cash

$ 0

Madsen Medical, Inc. Litigation [Member]

Loss Contingencies [Line Items]

Loss contingency, settlement agreement, court

On March 18, 2016, the trial court entered judgment in favor of MMI in the amount of $27.8 million, which amount excluded the $14.0 million disgorgement awarded by the jury.

Loss contingency, estimate of possible loss

$ 0

Jury award

$ 27,800,000

Madsen Medical, Inc. Litigation [Member] | Loss Profits for Tortious Interference [Member]

Loss Contingencies [Line Items]

Jury award

$ 7,500,000

Madsen Medical, Inc. Litigation [Member] | Unjust Enrichment [Member]

Loss Contingencies [Line Items]

Jury award

14,000,000

Madsen Medical, Inc. Litigation [Member] | Punitive Damages [Member]

Loss Contingencies [Line Items]

Jury award

20,000,000

Madsen Medical, Inc. Litigation [Member] | Damages for Breach of Contract [Member]

Loss Contingencies [Line Items]

Jury award

$ 300,000

Regulatory Matters (Details Tex

Regulatory Matters (Details Textual) - USD ($)	1 Months Ended	3 Months Ended
	Jul. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Regulatory Asset [Line Items]
Liability related to settlement with OIG		$ 0	$ 42,575,000
OIG [Member]
Regulatory Asset [Line Items]
Liability related to settlement with OIG			$ 13,800,000
Definitive settlement agreement payable	$ 13,500,000
Fees and accrued interest	$ 300,000