Abiomed (ABMD) 10-Q 4 Nov 15 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Trading Symbol	ABMD
Entity Registrant Name	ABIOMED INC
Entity Central Index Key	815,094
Current Fiscal Year End Date	--03-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		42,417,469

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Current assets:
Cash and cash equivalents	$ 54,421	$ 22,401
Short-term marketable securities	121,087	109,557
Accounts receivable, net	37,119	31,828
Inventories	23,032	16,774
Prepaid expenses and other current assets	4,030	4,479
Deferred tax assets, net	25,715	35,100
Total current assets	265,404	220,139
Long-term marketable securities		13,996
Property and equipment, net	11,420	9,127
Goodwill	32,676	31,534
In-Process Research and Development	15,243	14,711
Long-term deferred tax assets, net	44,240	45,206
Other assets	4,423	3,654
Total assets	373,406	338,367
Current liabilities:
Accounts payable	8,788	10,389
Accrued expenses	18,861	21,894
Deferred revenue	6,803	7,036
Total current liabilities	34,452	39,319
Other long-term liabilities	217	183
Contingent consideration	6,817	6,510
Long-term deferred tax liabilities	824	795
Total liabilities	$ 42,310	$ 46,807
Commitments and contingencies (Note 10)
Stockholders' equity:
Class B Preferred Stock, $.01 par value Authorized - 1,000,000 shares; Issued and outstanding - none
Common stock, $.01 par value Authorized - 100,000,000 shares; Issued - 43,756,550 shares at September 30, 2015 and 42,618,717 shares at March 31, 2015; Outstanding - 42,417,469 shares at September 30, 2015 and 41,335,773 shares at March 31, 2015	$ 424	$ 413
Additional paid in capital	489,463	465,046
Accumulated deficit	(120,628)	(137,222)
Treasury stock at cost - 1,339,081 shares at September 30, 2015 and 1,282,944 shares at March 31, 2015	(23,157)	(19,347)
Accumulated other comprehensive loss	(15,006)	(17,330)
Total stockholders' equity	331,096	291,560
Total liabilities and stockholders' equity	$ 373,406	$ 338,367

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2015	Mar. 31, 2015
Class B Preferred Stock, par value	$ 0.01	$ 0.01
Class B Preferred Stock, Authorized	1,000,000	1,000,000
Class B Preferred Stock, Issued	0	0
Class B Preferred Stock, outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, Authorized	100,000,000	100,000,000
Common stock, Issued	43,756,550	42,618,717
Common stock, Outstanding	42,417,469	41,335,773
Treasury stock, shares	1,339,081	1,282,944

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue:
Product revenue	$ 76,354	$ 51,774	$ 149,780	$ 100,434
Funded research and development	5	164	11	315
Total Revenue	76,359	51,938	149,791	100,749
Costs and expenses:
Cost of product revenue	12,144	9,612	23,012	19,301
Research and development	11,569	8,693	21,779	17,755
Selling, general and administrative	39,829	29,455	77,152	61,053
Costs and Expenses, Total	63,542	47,760	121,943	98,109
Income from operations	12,817	4,178	27,848	2,640
Other income (loss):
Investment income, net	62	36	125	80
Other income (loss), net	87	(39)	140	(28)
Nonoperating Income (Expense), Total	149	(3)	265	52
Income before income taxes	12,966	4,175	28,113	2,692
Income tax provision	5,231	336	11,519	562
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Basic net income per share	$ 0.18	$ 0.09	$ 0.40	$ 0.05
Basic weighted average shares outstanding	42,228	40,448	41,963	40,256
Diluted net income per share	$ 0.17	$ 0.09	$ 0.37	$ 0.05
Diluted weighted average shares outstanding	44,922	42,239	44,778	42,069

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Other comprehensive income:
Foreign currency translation gains (losses)	710	(4,804)	2,308	(5,240)
Net unrealized gains (losses) on marketable securities	6	(22)	16	5
Other comprehensive income (loss)	716	(4,826)	2,324	(5,235)
Comprehensive income (loss)	$ 8,451	$ (987)	$ 18,918	$ (3,105)

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating activities:
Net income	$ 16,594	$ 2,130
Adjustments required to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,352	1,196
Bad debt (recovery) expense	(18)	27
Stock-based compensation	15,592	8,314
Write-down of inventory	952	559
Excess tax benefit from stock-based awards	(383)
Deferred tax provision	10,803	450
Change in fair value of contingent consideration	307	219
Changes in assets and liabilities:
Accounts receivable	(5,214)	1,108
Inventories	(6,855)	(653)
Prepaid expenses and other assets	456	(139)
Accounts payable	(1,817)	(581)
Accrued expenses and other long-term liabilities	(2,674)	(3,732)
Deferred revenue	(239)	1,004
Net cash provided by operating activities	28,856	9,902
Investing activities:
Purchases of marketable securities	(99,002)	(44,920)
Proceeds from the sale and maturity of marketable securities	101,453	47,890
Acquisition of ECP and AIS, net of cash assumed		(15,697)
Purchase of other investment	(750)	(750)
Purchases of property and equipment	(3,419)	(1,496)
Net cash used for investing activities	(1,718)	(14,973)
Financing activities:
Proceeds from the exercise of stock options	7,971	2,560
Excess tax benefit from stock-based awards	383
Taxes paid related to net share settlement of vesting of stock awards	(3,810)	(1,013)
Proceeds from the issuance of stock under employee stock purchase plan	451	397
Net cash provided by financing activities	4,995	1,944
Effect of exchange rate changes on cash	(113)	(306)
Net increase (decrease) in cash and cash equivalents	32,020	(3,433)
Cash and cash equivalents at beginning of period	22,401	20,916
Cash and cash equivalents at end of period	54,421	17,483
Supplemental disclosure of cash flow information:
Cash paid for income taxes	576	299
Supplemental disclosure of non-cash investing and financing activities:
Contingent consideration related to acquisition of ECP		6,000
Property and equipment in accounts payable and accrued expenses	$ 396	$ 577

Nature of Business and Basis of

Nature of Business and Basis of Preparation	6 Months Ended
	Sep. 30, 2015
Nature of Business and Basis of Preparation	Note 1. Nature of Business and Basis of Preparation Abiomed, Inc. (the “Company”) is a leading provider of mechanical circulatory support devices and offers a continuum of care to heart failure patients. The Company develops, manufactures and markets proprietary products that are designed to enable the heart to rest, heal and recover by improving blood flow and/or performing the pumping function of the heart. The Company’s products are used in the cardiac catheterization lab, or cath lab, by interventional cardiologists and in the heart surgery suite by heart surgeons for patients who are in need of hemodynamic support prophylactically or emergently before, during or after angioplasty or heart surgery procedures. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP, for interim financial reporting and in accordance with Article 10 of Regulation S-X. Accordingly, they do not include all of the information and note disclosures required by GAAP for complete financial statements. These statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2015 that has been filed with the Securities and Exchange Commission (the “SEC”). In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments, which are of a normal recurring nature and are necessary for a fair presentation of results for the interim periods presented. The results of operations for any interim period may not be indicative of results for the full fiscal year or any other subsequent period. There have been no changes in the Company’s significant accounting policies for the three and six months ended September 30, 2015 as compared to the significant accounting policies described in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2015 that has been filed with the SEC. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory

Net Income Per Share

Net Income Per Share	6 Months Ended
	Sep. 30, 2015
Net Income Per Share	Note 2. Net Income Per Share Basic net income per share is computed by dividing net income by the weighted average number of common shares outstanding during the period. Diluted net income per share is computed by dividing net income by the weighted average number of dilutive common shares outstanding during the period. Diluted shares outstanding are calculated by adding to the weighted average shares outstanding any potential dilutive securities outstanding for the period. Potential dilutive securities include stock options, restricted stock units, performance-based stock awards and shares to be purchased under the Company’s employee stock purchase plan. In periods when a net loss is reported, all common stock equivalents are excluded from the calculation because they would have an anti-dilutive effect, meaning the loss per share would be reduced. Therefore, in periods when a loss is reported, basic and dilutive loss per share are the same. The Company’s basic and diluted net income per share for the three and six months ended September 30, 2015 and 2014 were as follows (in thousands, except per share data): For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Basic Net Income Per Share Net income $ 7,735 $ 3,839 $ 16,594 $ 2,130 Weighted average shares used in computing basic net income per share 42,228 40,448 41,963 40,256 Net income per share - basic $ 0.18 $ 0.09 $ 0.40 $ 0.05 For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Diluted Net Income Per Share Net income $ 7,735 $ 3,839 $ 16,594 $ 2,130 Weighted average shares used in computing basic net income per share 42,228 40,448 41,963 40,256 Effect of dilutive securities 2,694 1,791 2,815 1,813 Weighted average shares used in computing diluted net income per share 44,922 42,239 44,778 42,069 Net income per share - diluted $ 0.17 $ 0.09 $ 0.37 $ 0.05 For the three and six months ended September 30, 2015, approximately 1,000 shares underlying out-of-the-money stock options were not included in the computation of diluted earnings per share because their effect would have been anti-dilutive. Also, approximately 227,000 and 226,000 restricted shares in the three and six months ended September 30, 2015, respectively, related to performance-based awards for which milestones have not been met, were not included in the computation of diluted earnings per share. For the three and six months ended September 30, 2014, approximately 47,000 and 44,000 shares, respectively, underlying out-of-the-money stock options were not included in the computation of diluted earnings per share because their effect would have been anti-dilutive. Also, approximately 465,000 restricted shares in each of the three and six months ended September 30, 2014 related to performance-based awards for which milestones had not been met, were not included in the computation of diluted earnings per share.

Acquisitions

Acquisitions	6 Months Ended
	Sep. 30, 2015
Acquisitions	Note 3. Acquisitions Acquisition of ECP Entwicklungsgesellschaft mbH On July 1, 2014, the Company entered into a share purchase agreement with its wholly owned German subsidiary, Abiomed Europe GmbH (“Abiomed Europe”) and Syscore GmbH (“Syscore”), a limited liability company located in Berlin, Germany, providing for the Company’s acquisition of all of the share capital of ECP Entwicklungsgesellschaft mbH (“ECP”), a limited liability company incorporated in Germany. ECP is engaged in research, development, prototyping and the production of a percutaneous expandable catheter pump which increases blood circulation from the heart with an external drive shaft. The Company’s acquisition of ECP closed on July 1, 2014. The Company acquired ECP for $13.0 million in cash, with additional potential payouts totaling $15.0 million payable to Syscore based on the achievement of certain technical, regulatory and commercial milestones. These milestone payments may be made, at the Company’s option, by a combination of cash or the Company’s common stock. With respect to such milestone payments, the share purchase agreement provides: • that, upon the earlier of (i) the Company’s receipt of European CE Marking approval relating to the sale of an expandable device based on certain patent rights acquired from ECP, or (ii) the Company’s bringing of a successful claim against a third party competitor (or reaching an economically equivalent settlement) for the infringement of certain patent rights acquired from ECP, it will pay Syscore an additional $7.0 million (provided that if such claim or settlement does not prohibit the third party competitor’s further marketing, production, sale, distribution, lease or use of any violating or infringing products, but only awards monetary damages to the Company or to Abiomed Europe, the amount payable to Syscore shall be limited to the lower of the amount of aggregate damages received and $7.0 million); and • that, upon the first to occur of (i) the Company’s successful commercialization of one or more rotatable and expandable devices based on certain patent rights acquired from ECP, where such devices achieve aggregate worldwide revenues of $125.0 million, including the revenues of third-party licensees, or (ii) the Company’s sale of (A) ECP, (B) all or substantially all of ECP’s assets, or (C) certain of ECP’s patent rights, the Company will pay to Syscore the lesser of (x) one-half of the profits earned from such sale described in the foregoing item (ii), after accounting for the costs of acquiring and operating ECP, or (y) $15.0 million (less any previous milestone payment). ECP’s Acquisition of AIS GmbH Aachen Innovative Solutions In connection with the Company’s acquisition of ECP, ECP acquired all of the share capital of AIS GmbH Aachen Innovative Solutions (“AIS”), a limited liability company incorporated in Germany, pursuant to a share purchase agreement dated as of June 30, 2014, by and among ECP and AIS’s four individual shareholders. AIS, based in Aachen, Germany, holds certain intellectual property useful to ECP’s business, and, prior to being acquired by ECP, had licensed such intellectual property to ECP. The purchase price for the acquisition of AIS’s share capital was approximately $2.8 million in cash, which was provided by the Company, and the acquisition closed immediately prior to Abiomed Europe’s acquisition of ECP. The share purchase agreement contains representations, warranties and closing conditions customary for transactions of its size and nature. Purchase Price Allocation The acquisition of ECP and AIS was accounted for as a business combination. The purchase price for the acquisition has been allocated to the assets acquired and liabilities assumed based on their estimated fair values. The acquisition-date fair value of the consideration transferred is as follows: Total Acquisition Date Fair Value (in thousands) Cash consideration $ 15,750 Contingent consideration 6,000 Total consideration transferred $ 21,750 The following table summarizes the estimated fair values of the assets acquired and liabilities assumed on July 1, 2014, the date of acquisition (in thousands): Acquired assets: Cash and cash equivalents $ 53 Accounts receivable 25 Property and equipment 619 In-process research and development 18,500 Goodwill 1,964 Long-term deferred tax assets 1,874 Other assets acquired 141 Total assets acquired 23,176 Liabilities assumed: Accounts payable 295 Accrued liabilities 131 Long-term deferred tax liabilities 1,000 Total liabilities assumed 1,426 Net assets acquired $ 21,750 In-process research and development (“IPR&D”) is the estimated fair value of the ECP and AIS technology that had either not reached commercial technological feasibility nor had alternative future use at the time of the acquisition. Therefore the Company considered IPR&D, with assigned values to be allocated among the various IPR&D assets acquired. Goodwill is calculated as the difference between the acquisition-date fair value of the consideration transferred and the fair values of the assets acquired and liabilities assumed. The goodwill resulting from these acquisitions arises largely from synergies expected from combining the operations of ECP and AIS with the Company’s existing operations. The goodwill is not deductible for income tax purposes.

Marketable Securities and Fair

Marketable Securities and Fair Value Measurements	6 Months Ended
	Sep. 30, 2015
Marketable Securities and Fair Value Measurements	Note 4. Marketable Securities and Fair Value Measurements Marketable Securities The Company’s marketable securities are classified as available-for-sale securities and, accordingly, are recorded at fair value. The difference between amortized cost and fair value is included in stockholders’ equity. The Company’s marketable securities at September 30, 2015 and March 31, 2015 are invested in the following: Amortized Gross Gross Fair (in $000’s) September 30, 2015: US Treasury mutual fund securities $ 19,487 $ — $ — $ 19,487 Short-term government-backed securities 101,588 14 (2 ) 101,600 $ 121,075 $ 14 $ (2 ) $ 121,087 Amortized Gross Gross Fair (in $000’s) March 31, 2015: US Treasury mutual fund securities $ 19,487 $ — $ — $ 19,487 Short-term government-backed securities 90,070 9 (9 ) 90,070 Long-term government-backed securities 13,999 2 (5 ) 13,996 $ 123,556 $ 11 $ (14 ) $ 123,553 Fair Value Hierarchy Fair value is defined as the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three categories: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. Level 1 primarily consists of financial instruments whose values are based on quoted market prices such as exchange-traded instruments and listed equities. Level 2 includes financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including time value, yield curve, volatility factors, prepayment speeds, default rates, loss severity, current market and contractual prices for the underlying financial instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. Level 3 is comprised of unobservable inputs that are supported by little or no market activity. Financial assets are considered Level 3 when their fair values are determined using pricing models, discounted cash flows, or similar techniques, and at least one significant model assumption or input is unobservable. The following table presents the Company’s financial instruments recorded at fair value in the condensed consolidated balance sheets, classified according to the three categories described above: Level 1 Level 2 Level 3 Total (in $000’s) September 30, 2015: Assets U.S. Treasury mutual fund securities $ — $ 19,487 $ — $ 19,487 Short-term government-backed securities — 101,600 — 101,600 Liabilities Contingent consideration — — 6,817 6,817 Level 1 Level 2 Level 3 Total (in $000’s) March 31, 2015: Assets U.S. Treasury mutual fund securities $ — $ 19,487 $ — $ 19,487 Short-term government-backed securities — 90,070 — 90,070 Long-term government-backed securities — 13,996 — 13,996 Liabilities Contingent consideration — — 6,510 6,510 The Company’s investments in U.S. Treasury mutual fund securities, short-term government-backed securities and long-term government-backed securities are reported as Level 2 financial assets as they are not exchange-traded instruments. The Company’s financial liabilities consisted of contingent consideration potentially payable to former ECP shareholders related to the acquisition of ECP in July 2014. This liability is reported as Level 3 as the estimated fair value of the contingent consideration related to the acquisition of the ECP requires significant management judgment or estimation and is calculated using the income approach, using various revenue and cost assumptions and applying a probability to each outcome. The following table summarizes the change in fair value, as determined by Level 3 inputs, of the contingent consideration for the six months ended September 30, 2015: For the Six Months Ended 2015 (in $000’s) Level 3 liabilities, beginning balance $ 6,510 Additions — Payments — Change in fair value 307 Level 3 liabilities, ending balance $ 6,817 The change in fair value of the contingent consideration of $0.2 million and $0.3 million for the three and six months ended September 30, 2015, respectively, and $0.2 million for each of the three and six months ended September 30, 2014, was due to an increase in fair value caused by the effect of the passage of time on the fair value measurement of milestones related to the ECP acquisition. Adjustments associated with the change in fair value of contingent consideration are included in research and development expenses on the Company’s condensed consolidated statements of operations. The following table presents quantitative information about the inputs and valuation methodologies used for the Company’s fair value measurements as of September 30, 2015 classified as Level 3: Fair Value at September 30, 2015 Significant Weighted Average (range, if (in $000’s) Valuation Methodology Unobservable Input applicable) Contingent consideration $ 6,817 Probability weighted income Milestone dates 2018 to 2021 Discount rate 8% to 12% Probability of Probability adjusted level of 40% for the base case scenario and 5% to 25% for various upside and downside scenarios Other Investments The Company periodically makes investments in private medical device companies that focus on heart failure and heart pump technologies. In July 2015, the Company invested $0.8 million for its participation in a preferred stock offering of a private medical technology company. The aggregate carrying amount of the Company’s other investments was $4.4 million and $3.6 million at each of September 30, 2015 and March 31, 2015, respectively, and is classified within other assets in the unaudited condensed consolidated balance sheets. These investments are accounted for using the cost method and are measured at fair value only if there are identified events or changes in circumstances that may have a significant adverse effect on the fair value of these investments.

Inventories

Inventories	6 Months Ended
	Sep. 30, 2015
Inventories	Note 5. Inventories The components of inventories are as follows: September 30, 2015 March 31, 2015 (in $000’s) Raw materials and supplies $ 8,479 $ 7,417 Work-in-progress 9,358 6,466 Finished goods 5,195 2,891 $ 23,032 $ 16,774 The Company’s inventories relate to its circulatory care product lines, primarily its Impella ®

Goodwill and In-Process Researc

Goodwill and In-Process Research and Development	6 Months Ended
	Sep. 30, 2015
Goodwill and In-Process Research and Development	Note 6. Goodwill and In-Process Research and Development Goodwill The carrying amount of goodwill at September 30, 2015 and March 31, 2015 was $32.7 million and $31.5 million, respectively, and has been recorded in connection with the Company’s acquisition of Impella Cardiosystems AG, or Impella Cardiosystems in May 2005 and ECP and AIS in July 2014. The goodwill activity is as follows: (in $000’s) Balance at March 31, 2015 $ 31,534 Foreign currency translation impact 1,142 Balance at September 30, 2015 $ 32,676 The Company evaluates goodwill at least annually at October 31, as well as whenever events or changes in circumstances suggest that the carrying amount may not be recoverable. The Company has no accumulated impairment losses on goodwill. As described in Note 3 “Acquisitions,” in July 2014, the Company acquired ECP and AIS and recorded $18.5 million of IPR&D. The estimated fair value of IPR&D was determined using a probability-weighted income approach, which discounts expected future cash flows to present value. The projected cash flows from the expandable catheter pump technology were based on certain key assumptions, including estimates of future revenue and expenses, taking into account the stage of development of the technology at the acquisition date and the time and resources needed to complete development. The Company used a discount rate of 22.5% and cash flows that have been probability adjusted to reflect the risks of product commercialization, which the Company believes are appropriate and representative of market participant assumptions. The carrying value of the Company’s IPR&D assets and the change in the balance for the six months ended September 30, 2015 are as follows: (in $000’s) Balance at March 31, 2015 $ 14,711 Foreign currency translation impact 532 Balance at September 30, 2015 $ 15,243

Accrued Expenses

Accrued Expenses	6 Months Ended
	Sep. 30, 2015
Accrued Expenses	Note 7. Accrued Expenses Accrued expenses consist of the following: September 30, 2015 March 31, 2015 (in $000’s) Employee compensation $ 11,343 $ 15,978 Research and development 2,957 1,744 Sales and income taxes 1,249 1,506 Professional, legal and accounting fees 1,112 710 Warranty 697 1,103 Other 1,503 853 $ 18,861 $ 21,894 Employee compensation consists primarily of accrued bonuses, accrued commissions and accrued employee benefits at September 30, 2015 and March 31, 2015.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Sep. 30, 2015
Stock-Based Compensation	Note 8. Stock-Based Compensation The following table summarizes stock-based compensation expense by financial statement line item in the Company’s condensed consolidated statements of operations for the three and six months ended September 30, 2015 and 2014: For the Three Months Ended For the Six Months Ended September 30, 2015 2014 2015 2014 (in $000’s) (in $000’s) Cost of product revenue $ 218 $ 148 $ 455 $ 357 Research and development 989 773 1,920 1,626 Selling, general and administrative 9,586 3,103 13,217 6,331 $ 10,793 $ 4,024 $ 15,592 $ 8,314 The components of stock-based compensation for the three and six months ended September 30, 2015 and 2014 were as follows: For the Three Months Ended September 30, For the Six Months Ended September 30, 2015 2014 2015 2014 (in $000’s) (in $000’s) Restricted stock units $ 8,446 $ 3,334 $ 12,349 $ 6,754 Stock options 2,227 624 3,046 1,423 Employee stock purchase plan 120 66 197 137 $ 10,793 $ 4,024 $ 15,592 $ 8,314 The Company’s former Chief Financial Officer retired effective July 31, 2015 and currently serves as a consultant to the Company through July 31, 2017. In connection with the former Chief Financial Officer’s retirement agreement, his unvested options and restricted stock units were modified such that they will continue to vest and he will be permitted to exercise any vested options until July 31, 2017, including any options that vest after his retirement date, other than such options that expire on the tenth anniversary of the grant date. The Company recorded costs of $2.5 million in stock compensation expense, which is recorded in selling, general and administrative expenses for the three and six months ended September 30, 2015. In June 2015, the Company’s Board of Directors adopted a non-employee director retirement policy that provides for the accelerated vesting of all stock options, restricted stock units and other equity awards held by a non-employee director if he or she permanently ceases his or her service on the Company’s Board of Directors by reason of death, disability, or the non-employee director’s retirement following at least five years of service and so long as his or her age plus service equals or exceeds 65. This retirement policy accelerated the recognition of stock-based compensation because the outstanding unvested restricted stock units held by retirement eligible non-employee directors are able to vest at their decision to retire. The Company recorded costs of $1.4 million in accelerated stock compensation expense, which is recorded in selling, general and administrative expenses for the six months ended September 30, 2015. In August 2015, the Company approved the annual equity award grant to non-employee directors in the form of restricted stock units covering 3,900 shares of the Company’s common stock, which vest on the earlier of: (a) the one year anniversary of the grant date; or (b) the next annual meeting of stockholders. In conjunction with the Company’s non-employee director retirement policy, the stock compensation expense for awards to retirement eligible non-employee directors was fully recognized upon grant. The Company recorded costs of $2.0 million in stock compensation expense, which is recorded in selling, general and administrative expenses for the three and six months ended September 30, 2015. Stock Options The following table summarizes the stock option activity for the six months ended September 30, 2015: Options (in thousands) Weighted Weighted Aggregate Outstanding at beginning of period 2,892 $ 14.72 5.18 Granted 145 69.50 Exercised (703 ) 11.33 Cancelled and expired (1 ) 14.00 Outstanding at end of period 2,333 $ 19.16 5.56 $ 172,712 Exercisable at end of period 1,696 $ 13.76 4.50 $ 134,674 Options vested and expected to vest at end of period 2,277 $ 18.98 5.50 $ 169,000 The aggregate intrinsic value of options exercised was $49.5 million for the six months ended September 30, 2015. The total fair value of options that vested during the six months ended September 30, 2015 was $2.4 million. The remaining unrecognized stock-based compensation expense for unvested stock option awards at September 30, 2015 was approximately $6.4 million, net of forfeitures, and the weighted-average period over which this cost will be recognized is 2.3 years. The Company estimates the fair value of each stock option granted at the grant date using the Black-Scholes option valuation model. The weighted average grant-date fair value for options granted during the six months ended September 30, 2015 and 2014 was $18.08 and $9.05 per share, respectively. The fair value of options granted during the three and six months ended September 30, 2015 and 2014 were calculated using the following weighted average assumptions: For the Three Months Ended September 30, For the Six Months Ended September 30, 2015 2014 2015 2014 Risk-free interest rate 1.63 % 1.75 % 1.59 % 1.60 % Expected option life (years) 4.13 4.19 4.14 4.19 Expected volatility 48.3 % 48.7 % 49.7 % 49.3 % The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant for a term consistent with the expected life of the stock options. Volatility assumptions are calculated based on the historical volatility of the Company’s stock and adjustments for factors not reflected in historical volatility that may be more indicative of future volatility. The Company estimates the expected term of options based on historical exercise experience and estimates of future exercises of unexercised options. An expected dividend yield of zero is used in the option valuation model because the Company does not pay cash dividends and does not expect to pay any cash dividends in the foreseeable future. The Company estimates forfeitures based on an analysis of actual historical forfeitures, adjusted to the extent historic forfeitures may not be indicative of forfeitures in the future. Restricted Stock and Restricted Stock Units The following table summarizes the activity of restricted stock and restricted stock units for the six months ended September 30, 2015: Number of Shares Weighted Average Grant Date Fair Value (in thousands) (per share) Restricted stock and restricted stock units at beginning of period 1,160 $ 21.90 Granted 655 $ 80.70 Vested (461 ) $ 22.55 Forfeited (42 ) $ 13.09 Restricted stock and restricted stock units at end of period 1,312 $ 51.31 As of September 30, 2015, there are no restricted stock awards outstanding. The weighted average grant-date fair value for restricted stock units granted, including performance and market-based awards, during the six months ended September 30, 2015 and 2014 was $80.70 and $21.88 per share, respectively. This includes 322,980 market based awards which were valued at $107.10 per share in which a Monte Carlo simulation was used to account for the market condition in valuing the award. See details below in “Market Based Awards”. The total fair value of restricted stock units that vested during the six months ended September 30, 2015 and 2014 was $10.2 million and $9.5 million, respectively. The remaining unrecognized compensation expense for outstanding restricted stock units, including performance and market-based awards, as of September 30, 2015 was $33.3 million and the weighted-average period over which this cost will be recognized is 2.8 years. Performance and Market-Based Awards Included in the restricted stock units activity are certain awards that vest subject to certain performance and market-based criteria. The remaining unrecognized compensation expense for outstanding performance and market-based restricted stock units as of September 30, 2015 was $22.7 million and the weighted-average period over which this cost will be recognized is 3.0 years. Performance-Based Awards In May 2015, performance-based awards of restricted stock units for the potential issuance of 183,940 shares of common stock were issued to certain executive officers and employees, all of which vest upon achievement of prescribed service milestones by the award recipients and performance milestones by the Company. As of September 30, 2015, the Company is recognizing compensation expense based on the probable outcome related to the prescribed performance targets on the outstanding awards. In May 2014, performance-based awards of restricted stock units for the potential issuance of 379,752 shares of common stock were issued to certain executive officers and employees, all of which vest upon achievement of prescribed service milestones by the award recipients and performance milestones by the Company. The Company met the prescribed performance milestones in fiscal 2015. As of September 30, 2015, 222,563 shares of common stock underlying restricted stock units remain unvested and such restricted stock units will vest subject to service requirements for vesting for these employees. In March 2014, the Company modified the performance condition on 50,000 restricted stock units originally granted in June 2011. During the three months ended June 30, 2015, the Company reversed $1.0 million that had been previously recorded as stock-based compensation expense based on the expectation that it is not probable that certain performance milestones related to this award will be achieved within the time period required by the award. In May 2013, performance-based awards of restricted stock units for the potential issuance of 268,988 shares of common stock were issued to certain executive officers and employees, all of which vest upon achievement of prescribed service milestones by the award recipients and performance milestones by the Company. The Company met the prescribed performance milestones in fiscal 2014. As of September 30, 2015, 148,995 shares of common stock underlying restricted stock units remain unvested and such restricted stock units will vest subject to service requirements for vesting for these employees. Market-Based Awards In June 2015, the Company awarded certain executive officers a total of up to 322,980 market-based restricted share units. These restricted stock units will vest and result in the issuance of common stock based on continuing employment and the relative ranking of the total shareholder return (“TSR”) of the Company’s common stock in relation to the TSR of the component companies in the S&P Health Care Equipment Select Industry Index over a three-year performance period based on a comparison of average closing stock prices between June 2015 and June 2018. The actual number of market-based restricted stock units that may be earned can range from 0% to 300% of the target number of shares. One-half of the market-based restricted stock units earned will vest in June 2018 and the remaining restricted stock units will vest one year thereafter. The Company used a Monte Carlo simulation model to estimate that the grant-date fair value of the restricted stock units. The fair value related to the restricted stock units will be recorded as stock compensation expense over the period from date of grant to June 2018 regardless of the actual TSR outcome achieved. The table below sets forth the assumptions used to value the awards and the estimated grant-date fair value: Risk-free interest rate 1.10 % Dividend yield 0 % Remaining performance period (years) 2.96 Expected volatility 47.2 % Estimated grant date fair value (per share) $ 107.10 Target performance (number of shares) 107,660

Income Taxes

Income Taxes	6 Months Ended
	Sep. 30, 2015
Income Taxes	Note 9. Income Taxes The income tax provision represents the Company’s federal and state income tax obligations as well as foreign tax provisions. The Company’s income tax provision was $5.2 million and $11.5 million for the three and six months ended September 30, 2015, respectively. The Company’s income tax provision was $0.3 million and $0.6 million for the three and six months ended September 30, 2014, respectively. The estimated annual effective income tax rate is based upon estimated income before income taxes for the year, the geographical composition of the estimated income before taxes and estimated permanent differences. The estimated annual effective income tax rate can fluctuate and may differ from the actual tax rate recognized in fiscal 2016 for various reasons, including estimates of income before taxes, tax legislation, permanent differences, discrete items, and any adjustments between tax provision calculations and filed tax returns. The significant differences between the statutory tax rate and effective tax rate for the three and six months ended September 30, 2015 and 2014 were as follows: For the Three Months Ended For the Six Months Ended September 30, 2015 2014 2015 2014 Statutory income tax rate 35.0 % 34.0 % 35.0 % 34.0 % Increase (decrease) resulting from: Losses not benefited — (26.0 ) — (15.7 ) Credits (1.2 ) — (1.4 ) — State taxes, net 3.3 — 3.3 — Permanent differences 3.0 — 3.5 — Other 0.2 — 0.6 2.6 Effective tax rate 40.3 % 8.0 % 41.0 % 20.9 % The Company and its subsidiaries are subject to U.S. federal income tax, as well as income taxes in Germany and multiple state jurisdictions. All tax years remain subject to examination by the Internal Revenue Service and state tax authorities, because the Company has net operating loss and tax credit carryforwards which may be utilized in future years to offset taxable income, those years may also be subject to review by relevant taxing authorities if the carryforwards are utilized. Fiscal years 2012 through 2015 remain open to examination in Germany.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Sep. 30, 2015
Commitments and Contingencies	Note 10. Commitments and Contingencies Commitments In April 2015, the Company entered into an amendment to lease an additional 24,560 square feet of space at its existing headquarters in Danvers, Massachusetts. The Company has certain rights to terminate the lease early, subject to the payment of a specified termination fee based on the timing of the termination, as further outlined in the lease amendment. The amendment also grants the Company a one-time right of first offer to lease new space in the facility and a one-time first right of refusal to buy the facility, subject to certain conditions set forth therein This facility encompasses most of the Company’s U.S. operations, including research and development, manufacturing, sales and marketing and general and administrative departments. The monthly lease payments over the term of the lease are as follows: • The base rent for May 2014 through December 2015 is $74,050 per month; and • The base rent for January 2016 through February 2016 will be $85,818 per month; and • The base rent for March 2016 through February 2018 will be $82,518 per month; and • The base rent for March 2018 through February 2021 will be $85,030 per month. The Company’s European headquarters is located in Aachen, Germany and consists of approximately 33,000 square feet of space under an operating lease. In July 2013, the Company entered into a lease agreement to continue renting its existing space in Aachen, Germany through July 31, 2023. In October 2015, the Company entered into an amendment to this lease agreement to lease 9,000 square feet of additional space effective July 1, 2015. The Company also entered into another lease agreement in October 2015 to lease approximately 30,000 square feet of additional space adjacent to its Aachen facility from July 1, 2015 through June 30, 2016. This agreement also provided the Company with options to extend the lease through July 31, 2033. The lease payments under these agreements are approximately 64,500€ (euro) (approximately U.S. $72,500 at September 30, 2015 exchange rates) per month. The building houses most of the manufacturing operations for the Impella product lines as well as certain research and development functions and the sales, marketing and general and administrative functions for most of its product lines sold in Europe and the Middle East. License Agreement In April 2014, the Company entered into an exclusive license agreement with Opsens, Inc. for the rights to certain optical sensor technologies in the field of cardio-circulatory assist devices. The Company made a $1.5 million upfront payment upon execution of the agreement and agreed to make additional payments of up to $4.5 million upon the achievement of certain development milestones. Litigation From time to time, the Company is involved in legal and administrative proceedings and claims of various types. In some actions, the claimants seek damages, as well as other relief, which, if granted, would require significant expenditures. The Company records a liability in its condensed consolidated financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in its condensed consolidated financial statements. On October 26, 2012, the Company was informed that the Department of Justice, United States Attorney’s Office for the District of Columbia was conducting an investigation (“Marketing and Labeling Investigation”) focused on the Company’s marketing and labeling of the Impella 2.5. On October 31, 2012, the Company accepted service of a subpoena related to this investigation seeking documents and other materials related to the Impella ® On April 25, 2014, the Company received a subpoena from the Boston regional office of the United States Department of Health and Human Services, or HHS, Office of Inspector General requesting materials relevant to the Company’s reimbursement of expenses and remuneration to healthcare providers for a six month period from July 2012 through December 2012 in connection with a civil investigation under the False Claims Act (the “FCA Investigation”). The Company submitted the requested documents to HHS and believes that it substantially complied with the subpoena. On November 6, 2014, the Company received notice from the Department of Justice, United States Attorney’s Office for the District of Massachusetts in the form of a Civil Investigative Demand (“CID”) requesting additional materials relating to this matter for the time period of January 1, 2012 through December 31, 2013. The Company is currently in the process of responding to the additional requests for information contained in the CID, and other informal requests, and intends to continue to cooperate with the U.S. Attorney’s Office in connection with the FCA Investigation. In July and August 2015, Thoratec Corporation (“Thoratec”), acquired by St. Jude Medical, Inc. in October 2015, brought actions in connection with two Company patents relevant to Thoratec’s HeartMate PHP (“Percutaneous Heart Pump”) medical device (“PHP”). In those proceedings, which are in the United Kingdom and Germany, Thoratec asserts that the two patents are invalid. In September 2015, the Company filed counterclaims in the action in Germany asserting that the PHP product infringes the two patents and a third patent owned by the Company. Both the Germany and United Kingdom proceedings are ongoing. The Company is unable to estimate a potential liability with respect to the legal matters noted above. There are numerous factors that make it difficult to meaningfully estimate possible loss or range of loss at this stage of the legal proceedings, including that the FCA Investigation and patent dispute with Thoratec remain in relatively early stages, there are significant factual and legal issues to be resolved and information obtained or rulings made during any potential lawsuits or investigations could affect the methodology for calculation. Therefore, the Company is unable at this time to estimate any possible losses and accordingly, no adjustment has been made to the financial statements to reflect the outcome of these uncertainties.

Segment and Enterprise Wide Dis

Segment and Enterprise Wide Disclosures	6 Months Ended
	Sep. 30, 2015
Segment and Enterprise Wide Disclosures	Note 11. Segment and Enterprise Wide Disclosures The Company operates in one business segment—the research, development and sale of medical devices to assist or replace the pumping function of the failing heart. The Company’s chief operating decision maker (determined to be the Chief Executive Officer) does not manage any part of the Company separately, and the allocation of resources and assessment of performance are based on the Company’s consolidated operating results. Approximately 77% of the Company’s total consolidated assets were located within the U.S. as of September 30, 2015 and March 31, 2015. The remaining assets were located primarily in Germany and included goodwill and IPR&D of $47.9 million and $46.2 million at September 30, 2015 and March 31, 2015, respectively, associated with the Impella Cardiosystems acquisition in May 2005 and the ECP acquisition in July 2014. Total assets outside of the U.S. excluding goodwill and IPR&D amounted to 10% of total consolidated assets as of each of September 30, 2015 and March 31, 2015. International sales (primarily in Europe) accounted for 7% of total revenue for each of the three and six months ended September 30, 2015 and 11% of total revenue for each of the three and six months ended September 30, 2014.

Nature of Business and Basis 18

Nature of Business and Basis of Preparation (Policies)	6 Months Ended
	Sep. 30, 2015
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory

Net Income Per Share (Tables)

Net Income Per Share (Tables)	6 Months Ended
	Sep. 30, 2015
Computation of Basic and Diluted Net Income Per Share	The Company’s basic and diluted net income per share for the three and six months ended September 30, 2015 and 2014 were as follows (in thousands, except per share data): For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Basic Net Income Per Share Net income $ 7,735 $ 3,839 $ 16,594 $ 2,130 Weighted average shares used in computing basic net income per share 42,228 40,448 41,963 40,256 Net income per share - basic $ 0.18 $ 0.09 $ 0.40 $ 0.05 For the Three Months Ended For the Six Months Ended 2015 2014 2015 2014 Diluted Net Income Per Share Net income $ 7,735 $ 3,839 $ 16,594 $ 2,130 Weighted average shares used in computing basic net income per share 42,228 40,448 41,963 40,256 Effect of dilutive securities 2,694 1,791 2,815 1,813 Weighted average shares used in computing diluted net income per share 44,922 42,239 44,778 42,069 Net income per share - diluted $ 0.17 $ 0.09 $ 0.37 $ 0.05

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Sep. 30, 2015
Fair Value of the Consideration Transferred	The acquisition-date fair value of the consideration transferred is as follows: Total Acquisition Date Fair Value (in thousands) Cash consideration $ 15,750 Contingent consideration 6,000 Total consideration transferred $ 21,750
Estimated Fair Values of the Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed on July 1, 2014, the date of acquisition (in thousands): Acquired assets: Cash and cash equivalents $ 53 Accounts receivable 25 Property and equipment 619 In-process research and development 18,500 Goodwill 1,964 Long-term deferred tax assets 1,874 Other assets acquired 141 Total assets acquired 23,176 Liabilities assumed: Accounts payable 295 Accrued liabilities 131 Long-term deferred tax liabilities 1,000 Total liabilities assumed 1,426 Net assets acquired $ 21,750

Marketable Securities and Fai21

Marketable Securities and Fair Value Measurements (Tables)	6 Months Ended
	Sep. 30, 2015
Marketable Securities	The Company’s marketable securities at September 30, 2015 and March 31, 2015 are invested in the following: Amortized Gross Gross Fair (in $000’s) September 30, 2015: US Treasury mutual fund securities $ 19,487 $ — $ — $ 19,487 Short-term government-backed securities 101,588 14 (2 ) 101,600 $ 121,075 $ 14 $ (2 ) $ 121,087 Amortized Gross Gross Fair (in $000’s) March 31, 2015: US Treasury mutual fund securities $ 19,487 $ — $ — $ 19,487 Short-term government-backed securities 90,070 9 (9 ) 90,070 Long-term government-backed securities 13,999 2 (5 ) 13,996 $ 123,556 $ 11 $ (14 ) $ 123,553
Financial Instruments Recorded at Fair Value	The following table presents the Company’s financial instruments recorded at fair value in the condensed consolidated balance sheets, classified according to the three categories described above: Level 1 Level 2 Level 3 Total (in $000’s) September 30, 2015: Assets U.S. Treasury mutual fund securities $ — $ 19,487 $ — $ 19,487 Short-term government-backed securities — 101,600 — 101,600 Liabilities Contingent consideration — — 6,817 6,817 Level 1 Level 2 Level 3 Total (in $000’s) March 31, 2015: Assets U.S. Treasury mutual fund securities $ — $ 19,487 $ — $ 19,487 Short-term government-backed securities — 90,070 — 90,070 Long-term government-backed securities — 13,996 — 13,996 Liabilities Contingent consideration — — 6,510 6,510
Change in Fair Value of Contingent Consideration as Determined by Level 3 Inputs	The following table summarizes the change in fair value, as determined by Level 3 inputs, of the contingent consideration for the six months ended September 30, 2015: For the Six Months Ended 2015 (in $000’s) Level 3 liabilities, beginning balance $ 6,510 Additions — Payments — Change in fair value 307 Level 3 liabilities, ending balance $ 6,817
Quantitative Information about Inputs and Valuation Methodologies Used for Fair Value Measurements Classified in Level 3	The following table presents quantitative information about the inputs and valuation methodologies used for the Company’s fair value measurements as of September 30, 2015 classified as Level 3: Fair Value at September 30, 2015 Significant Weighted Average (range, if (in $000’s) Valuation Methodology Unobservable Input applicable) Contingent consideration $ 6,817 Probability weighted income Milestone dates 2018 to 2021 Discount rate 8% to 12% Probability of Probability adjusted level of 40% for the base case scenario and 5% to 25% for various upside and downside scenarios

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Sep. 30, 2015
Components of Inventories	The components of inventories are as follows: September 30, 2015 March 31, 2015 (in $000’s) Raw materials and supplies $ 8,479 $ 7,417 Work-in-progress 9,358 6,466 Finished goods 5,195 2,891 $ 23,032 $ 16,774

Goodwill and In-Process Resea23

Goodwill and In-Process Research and Development (Tables)	6 Months Ended
	Sep. 30, 2015
Goodwill Activity	The goodwill activity is as follows: (in $000’s) Balance at March 31, 2015 $ 31,534 Foreign currency translation impact 1,142 Balance at September 30, 2015 $ 32,676
Carrying value of In-Process Research and Development	The carrying value of the Company’s IPR&D assets and the change in the balance for the six months ended September 30, 2015 are as follows: (in $000’s) Balance at March 31, 2015 $ 14,711 Foreign currency translation impact 532 Balance at September 30, 2015 $ 15,243

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Sep. 30, 2015
Accrued Expenses	Accrued expenses consist of the following: September 30, 2015 March 31, 2015 (in $000’s) Employee compensation $ 11,343 $ 15,978 Research and development 2,957 1,744 Sales and income taxes 1,249 1,506 Professional, legal and accounting fees 1,112 710 Warranty 697 1,103 Other 1,503 853 $ 18,861 $ 21,894

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Sep. 30, 2015
Stock-Based Compensation Recognized	The following table summarizes stock-based compensation expense by financial statement line item in the Company’s condensed consolidated statements of operations for the three and six months ended September 30, 2015 and 2014: For the Three Months Ended For the Six Months Ended September 30, 2015 2014 2015 2014 (in $000’s) (in $000’s) Cost of product revenue $ 218 $ 148 $ 455 $ 357 Research and development 989 773 1,920 1,626 Selling, general and administrative 9,586 3,103 13,217 6,331 $ 10,793 $ 4,024 $ 15,592 $ 8,314
Components of Stock-Based Compensation	The components of stock-based compensation for the three and six months ended September 30, 2015 and 2014 were as follows: For the Three Months Ended September 30, For the Six Months Ended September 30, 2015 2014 2015 2014 (in $000’s) (in $000’s) Restricted stock units $ 8,446 $ 3,334 $ 12,349 $ 6,754 Stock options 2,227 624 3,046 1,423 Employee stock purchase plan 120 66 197 137 $ 10,793 $ 4,024 $ 15,592 $ 8,314
Summary of Stock Option Activity	The following table summarizes the stock option activity for the six months ended September 30, 2015: Options (in thousands) Weighted Weighted Aggregate Outstanding at beginning of period 2,892 $ 14.72 5.18 Granted 145 69.50 Exercised (703 ) 11.33 Cancelled and expired (1 ) 14.00 Outstanding at end of period 2,333 $ 19.16 5.56 $ 172,712 Exercisable at end of period 1,696 $ 13.76 4.50 $ 134,674 Options vested and expected to vest at end of period 2,277 $ 18.98 5.50 $ 169,000
Weighted-Average Assumptions Used to Calculate Fair Value of Options Granted	The fair value of options granted during the three and six months ended September 30, 2015 and 2014 were calculated using the following weighted average assumptions: For the Three Months Ended September 30, For the Six Months Ended September 30, 2015 2014 2015 2014 Risk-free interest rate 1.63 % 1.75 % 1.59 % 1.60 % Expected option life (years) 4.13 4.19 4.14 4.19 Expected volatility 48.3 % 48.7 % 49.7 % 49.3 %
Time Based Restricted Stock and Restricted Stock Units
Summary of Restricted Stock and Restricted Stock Units Activity	The following table summarizes the activity of restricted stock and restricted stock units for the six months ended September 30, 2015: Number of Shares Weighted Average Grant Date Fair Value (in thousands) (per share) Restricted stock and restricted stock units at beginning of period 1,160 $ 21.90 Granted 655 $ 80.70 Vested (461 ) $ 22.55 Forfeited (42 ) $ 13.09 Restricted stock and restricted stock units at end of period 1,312 $ 51.31
Restricted stock units
Monte Carlo Simulation Model to Estimate Grant-Date Fair Value of Restricted Stock Units	The table below sets forth the assumptions used to value the awards and the estimated grant-date fair value: Risk-free interest rate 1.10 % Dividend yield 0 % Remaining performance period (years) 2.96 Expected volatility 47.2 % Estimated grant date fair value (per share) $ 107.10 Target performance (number of shares) 107,660

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Sep. 30, 2015
Differences Between Statutory Income Tax Rate and Effective Tax Rates	The significant differences between the statutory tax rate and effective tax rate for the three and six months ended September 30, 2015 and 2014 were as follows: For the Three Months Ended For the Six Months Ended September 30, 2015 2014 2015 2014 Statutory income tax rate 35.0 % 34.0 % 35.0 % 34.0 % Increase (decrease) resulting from: Losses not benefited — (26.0 ) — (15.7 ) Credits (1.2 ) — (1.4 ) — State taxes, net 3.3 — 3.3 — Permanent differences 3.0 — 3.5 — Other 0.2 — 0.6 2.6 Effective tax rate 40.3 % 8.0 % 41.0 % 20.9 %

Computation of Basic and Dilute

Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basic Net Income Per Share
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Weighted average shares used in computing basic net income per share	42,228	40,448	41,963	40,256
Net income per share - basic	$ 0.18	$ 0.09	$ 0.40	$ 0.05
Diluted Net Income Per Share
Net income	$ 7,735	$ 3,839	$ 16,594	$ 2,130
Weighted average shares used in computing basic net income per share	42,228	40,448	41,963	40,256
Effect of dilutive securities	2,694	1,791	2,815	1,813
Weighted average shares used in computing diluted net income per share	44,922	42,239	44,778	42,069
Net income per share - diluted	$ 0.17	$ 0.09	$ 0.37	$ 0.05

Net Income Per Share - Addition

Net Income Per Share - Additional Information (Detail) - shares	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the calculation of diluted weighted average shares outstanding	1,000	47,000	1,000	44,000
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the calculation of diluted weighted average shares outstanding	227,000	465,000	226,000	465,000

Acquisitions - Additional Infor

Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands	Jul. 01, 2014	Sep. 30, 2015
Business Acquisition [Line Items]
Payments to acquire businesses, cash paid	$ 15,750
ECP Entwicklungsgesellschaft mbH
Business Acquisition [Line Items]
Business acquisition, date of acquisition agreement		Jul. 1, 2014
Payments to acquire businesses, cash paid	13,000
Potential payouts payments	15,000
Business combination, contingent consideration arrangements, descriptions		With respect to such milestone payments, the share purchase agreement provides:•that, upon the earlier of (i) the Company’s receipt of European CE Marking approval relating to the sale of an expandable device based on certain patent rights acquired from ECP, or (ii) the Company’s bringing of a successful claim against a third party competitor (or reaching an economically equivalent settlement) for the infringement of certain patent rights acquired from ECP, it will pay Syscore an additional $7.0 million (provided that if such claim or settlement does not prohibit the third party competitor’s further marketing, production, sale, distribution, lease or use of any violating or infringing products, but only awards monetary damages to the Company or to Abiomed Europe, the amount payable to Syscore shall be limited to the lower of the amount of aggregate damages received and $7.0 million); and•that, upon the first to occur of (i) the Company’s successful commercialization of one or more rotatable and expandable devices based on certain patent rights acquired from ECP, where such devices achieve aggregate worldwide revenues of $125.0 million, including the revenues of third-party licensees, or (ii) the Company’s sale of (A) ECP, (B) all or substantially all of ECP’s assets, or (C) certain of ECP’s patent rights, the Company will pay to Syscore the lesser of (x) one-half of the profits earned from such sale described in the foregoing item (ii), after accounting for the costs of acquiring and operating ECP, or (y) $15.0 million (less any previous milestone payment).
Expense due to infringement of certain patent rights acquired	7,000
Aggregate worldwide revenues, including revenues of third party licensees, targeted to be met for milestone payments	125,000
AIS GmbH Aachen Innovative Solutions
Business Acquisition [Line Items]
Business acquisition, date of acquisition agreement		Jun. 30, 2014
Payments to acquire businesses, cash paid	$ 2,800

Fair Value of the Consideration

Fair Value of the Consideration Transferred (Detail) $ in Thousands	Jul. 01, 2014USD ($)
Business Acquisition [Line Items]
Cash consideration	$ 15,750
Contingent consideration	6,000
Total consideration transferred	$ 21,750

Estimated Fair Values of the As

Estimated Fair Values of the Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015	Jul. 01, 2014
Acquired assets:
Goodwill	$ 32,676	$ 31,534
Long-term deferred tax assets	$ 44,240	$ 45,206
ECP
Acquired assets:
Cash and cash equivalents			$ 53
Accounts receivable			25
Property and equipment			619
In-process research and development			18,500
Goodwill			1,964
Long-term deferred tax assets			1,874
Other assets acquired			141
Total assets acquired			23,176
Liabilities assumed:
Accounts payable			295
Accrued liabilities			131
Long-term deferred tax liabilities			1,000
Total liabilities assumed			1,426
Net assets acquired			$ 21,750

Investable Marketable Securitie

Investable Marketable Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
US Treasury mutual fund Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Market Value	$ 19,487	$ 19,487
US Government-sponsored Enterprises Debt Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Market Value	101,600	90,070
US Government-sponsored Enterprises Debt Securities | Long-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Market Value		13,996
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	121,075	123,556
Gross Unrealized Gains	14	11
Gross Unrealized Losses	(2)	(14)
Fair Market Value	121,087	123,553
Level 2 | US Treasury mutual fund Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	19,487	19,487
Fair Market Value	19,487	19,487
Level 2 | US Government-sponsored Enterprises Debt Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	101,588	90,070
Gross Unrealized Gains	14	9
Gross Unrealized Losses	(2)	(9)
Fair Market Value	$ 101,600	90,070
Level 2 | US Government-sponsored Enterprises Debt Securities | Long-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		13,999
Gross Unrealized Gains		2
Gross Unrealized Losses		(5)
Fair Market Value		$ 13,996

Financial Instruments Recorded

Financial Instruments Recorded at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ 6,817	$ 6,510
US Treasury mutual fund Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure	19,487	19,487
US Government-sponsored Enterprises Debt Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure	101,600	90,070
US Government-sponsored Enterprises Debt Securities | Long-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure		13,996
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure	121,087	123,553
Level 2 | US Treasury mutual fund Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure	19,487	19,487
Level 2 | US Government-sponsored Enterprises Debt Securities | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure	101,600	90,070
Level 2 | US Government-sponsored Enterprises Debt Securities | Long-term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, fair value disclosure		13,996
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ 6,817	$ 6,510

Change in Fair Value of Conting

Change in Fair Value of Contingent Consideration as Determined by Level 3 Inputs (Detail) - Contingent Consideration - ECP Entwicklungsgesellschaft mbH - Level 3 $ in Thousands	6 Months Ended
	Sep. 30, 2015USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3 liabilities, beginning balance	$ 6,510
Additions	0
Payments	0
Change in fair value	307
Level 3 liabilities, ending balance	$ 6,817

Marketable Securities and Fai35

Marketable Securities and Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 31, 2015	Mar. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of the contingent consideration	$ 200	$ 200	$ 307	$ 219
Aggregate carrying amount of other investment	4,423		4,423			$ 3,654
Other assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate carrying amount of other investment	$ 4,400		$ 4,400			$ 3,600
Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investment, fair value					$ 800

Quantitative Information about

Quantitative Information about Inputs and Valuation Methodologies Used for Fair Value Measurements Classified in Level 3 (Detail) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Jul. 31, 2014	Sep. 30, 2015	Mar. 31, 2015
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration		$ 6,817	$ 6,510
Discount rate	22.50%
Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration		6,817	$ 6,510
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration		$ 6,817
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach | Contingent Consideration | Base Case Scenario
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Probability of occurrence		40.00%
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach | Contingent Consideration | Minimum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Milestone date		2,018
Discount rate		8.00%
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach | Contingent Consideration | Minimum | Various Upside and Downside Scenarios
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Probability of occurrence		5.00%
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach | Contingent Consideration | Maximum
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Milestone date		2,021
Discount rate		12.00%
ECP Entwicklungsgesellschaft mbH | Level 3 | Probability weighted income approach | Contingent Consideration | Maximum | Various Upside and Downside Scenarios
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Probability of occurrence		25.00%

Components of Inventories (Deta

Components of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Inventory [Line Items]
Raw materials and supplies	$ 8,479	$ 7,417
Work-in-progress	9,358	6,466
Finished goods	5,195	2,891
Inventories	$ 23,032	$ 16,774

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Inventory [Line Items]
Write-down of inventory	$ 952	$ 559

Goodwill and In-Process Resea39

Goodwill and In-Process Research and Development - Additional Information (Detail) - USD ($)	1 Months Ended
	Jul. 31, 2014	Sep. 30, 2015	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill		$ 32,676,000	$ 31,534,000
Accumulated impairment loss, goodwill		0
In-Process Research and Development	$ 18,500,000	$ 15,243,000	$ 14,711,000
Fair value inputs, discount rate	22.50%

Goodwill Activity (Detail)

Goodwill Activity (Detail) $ in Thousands	6 Months Ended
	Sep. 30, 2015USD ($)
Goodwill [Line Items]
Beginning balance	$ 31,534
Foreign currency translation impact	1,142
Ending balance	32,676
IPR&D
Goodwill [Line Items]
Beginning balance	14,711
Foreign currency translation impact	532
Ending balance	$ 15,243

Accrued Expenses (Detail)

Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Payables and Accruals [Abstract]
Employee compensation	$ 11,343	$ 15,978
Research and development	2,957	1,744
Sales and income taxes	1,249	1,506
Professional, legal and accounting fees	1,112	710
Warranty	697	1,103
Other	1,503	853
Accrued expenses	$ 18,861	$ 21,894

Stock-Based Compensation Recogn

Stock-Based Compensation Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 10,793	$ 4,024	$ 15,592	$ 8,314
Cost of product revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	218	148	455	357
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	989	773	1,920	1,626
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 9,586	$ 3,103	$ 13,217	$ 6,331

Components of Stock-Based Compe

Components of Stock-Based Compensation (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 10,793	$ 4,024	$ 15,592	$ 8,314
Restricted stock units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	8,446	3,334	12,349	6,754
Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	2,227	624	3,046	1,423
Employee Stock Purchase Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 120	$ 66	$ 197	$ 137

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended					3 Months Ended			6 Months Ended
	Jun. 30, 2015	May. 31, 2015	May. 31, 2014	Mar. 31, 2014	May. 31, 2013	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Aug. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation						$ 10,793		$ 4,024	$ 15,592	$ 8,314
Aggregate intrinsic value of options exercised in period									49,500
Fair value of options vested in period									$ 2,400
Weighted average grant-date fair value for options granted									$ 18.08	$ 9.05
Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employment retirement date									Jul. 31, 2015
Stock-based compensation						2,500			$ 2,500
Consultant service ending date									Jul. 31, 2017
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation						2,227		$ 624	$ 3,046	$ 1,423
Unrecognized stock-based compensation expense						$ 6,400			$ 6,400
Unrecognized stock-based compensation expense, weighted-average recognition period									2 years 3 months 18 days
Expected dividend yield									0.00%
Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share unit issued		183,940	379,752		268,988
Non-vested shares, outstanding						222,563		148,995	222,563	148,995
Shares of award granted, it is probable that the prescribed performance targets will be met				50,000
Reversal, Share based compensation							$ 1,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation						$ 8,446		$ 3,334	$ 12,349	$ 6,754
Years of service	5 years
Non-employee director retirement age	65 years
Unrecognized stock-based compensation expense						33,300			$ 33,300
Unrecognized stock-based compensation expense, weighted-average recognition period									2 years 9 months 18 days
Expected dividend yield									0.00%
Weighted average grant-date fair value for restricted stock and restricted stock units granted									$ 80.70	$ 21.88
Fair value of restricted stock and restricted stock units vested in period									$ 10,200	$ 9,500
Restricted stock units | Non-employee directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation						$ 2,000	$ 1,400		$ 2,000
Equity award, restricted stocks available for grant											3,900
Equity award, vesting options									Vest on the earlier of (a) the one year anniversary of the grant date; or (b) the next annual meeting of stockholders.
Market Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value for restricted stock and restricted stock units granted									$ 107.10
Restricted share unit issued									322,980
Market Based Restricted Stock Units | Executive Office
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share unit issued	322,980
Market Based Restricted Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Share earning						0.00%			0.00%
Market Based Restricted Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Share earning						300.00%			300.00%
Performance and Market-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense						$ 22,700			$ 22,700
Unrecognized stock-based compensation expense, weighted-average recognition period									3 years

Summary of Stock Option Activit

Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Sep. 30, 2015	Mar. 31, 2015
Options
Outstanding at beginning of period	2,892
Granted	145
Exercised	(703)
Cancelled and expired	(1)
Outstanding at end of period	2,333	2,892
Exercisable at end of period	1,696
Options vested and expected to vest at end of period	2,277
Weighted-Average Exercise Price
Outstanding at beginning of period	$ 14.72
Granted	69.50
Exercised	11.33
Cancelled and expired	14
Outstanding at end of period	19.16	$ 14.72
Exercisable at end of period	13.76
Options vested and expected to vest at end of period	$ 18.98
Weighted-Average Remaining Contractual Term (years)
Outstanding	5 years 6 months 22 days	5 years 2 months 5 days
Exercisable at end of period	4 years 6 months
Options vested and expected to vest at end of period	5 years 6 months
Aggregate Intrinsic Value
Outstanding at end of period	$ 172,712
Exercisable at end of period	134,674
Options vested and expected to vest at end of period	$ 169,000

Weighted Average Assumptions Us

Weighted Average Assumptions Used to Calculate Fair Value of Options Granted (Detail) - Stock Options	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate	1.63%	1.75%	1.59%	1.60%
Expected option life (years)	4 years 1 month 17 days	4 years 2 months 9 days	4 years 1 month 21 days	4 years 2 months 9 days
Expected volatility	48.30%	48.70%	49.70%	49.30%

Summary of Restricted Stock and

Summary of Restricted Stock and Time Based Restricted Stock Units Activity (Detail) - Restricted Stock and Restricted Stock Units shares in Thousands	6 Months Ended
	Sep. 30, 2015$ / sharesshares
Number of Shares
Beginning Balance	1,160
Granted	655
Vested	(461)
Forfeited	(42)
Ending Balance	1,312
Weighted Average Grant Date Fair Value
Beginning Balance | $ / shares	$ 21.90
Granted | $ / shares	80.70
Vested | $ / shares	22.55
Forfeited | $ / shares	13.09
Ending Balance | $ / shares	$ 51.31

Monte Carlo Simulation Model to

Monte Carlo Simulation Model to Estimate Grant-Date Fair Value of Restricted Stock Units (Detail) - Restricted stock units	6 Months Ended
	Sep. 30, 2015$ / sharesshares
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]
Risk-free interest rate	1.10%
Dividend yield	0.00%
Remaining performance period (years)	2 months 29 days
Expected volatility	47.20%
Estimated grant date fair value (per share) | $ / shares	$ 107.10
Target performance (number of shares)	107,660

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Taxes [Line Items]
Income tax provision	$ 5,231	$ 336	$ 11,519	$ 562

Differences Between Statutory I

Differences Between Statutory Income Tax Rate and Effective Tax Rates (Detail)	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schedule of Effective Tax Rate Reconciliation [Line Items]
Statutory income tax rate	35.00%	34.00%	35.00%	34.00%
Losses not benefited		(26.00%)		(15.70%)
Credits	(1.20%)		(1.40%)
State taxes, net	3.30%		3.30%
Permanent differences	3.00%		3.50%
Other	0.20%		0.60%	2.60%
Effective tax rate	40.30%	8.00%	41.00%	20.90%

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended
	Oct. 31, 2015ft²	Sep. 30, 2015USD ($)Patent	Jul. 31, 2013ft²	Sep. 30, 2015EUR (€)	Apr. 30, 2015ft²	Apr. 30, 2014USD ($)
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²					24,560
License agreement, upfront payment						$ 1,500,000
License agreement, maximum agreed additional payments upon achievement of development milestones						$ 4,500,000
Patents allegedly infringed upon, number | Patent		2
For May 2014 through December 2015
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month		$ 74,050
For January 2016 through February 2016
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month		85,818
For March 2016 through February 2018
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month		82,518
For March 2018 through February 2021
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month		85,030
Europe
Commitments and Contingencies [Line Items]
Facilities leases, base rent per month		$ 72,500		€ 64,500
Europe | Lease Agreements
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²			33,000
Lease, expiration date			Jul. 31, 2023
Subsequent Event | Europe | Lease Agreements
Commitments and Contingencies [Line Items]
Additional office space under operating lease | ft²	9,000
Subsequent Event | Europe | Lease Agreement Adjacent to Aachen Facility
Commitments and Contingencies [Line Items]
Office space under operating lease | ft²	30,000
Lease, expiration date	Jun. 30, 2016

Segment and Enterprise Wide D52

Segment and Enterprise Wide Disclosures - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015USD ($)	Sep. 30, 2014	Sep. 30, 2015USD ($)Segment	Sep. 30, 2014	Mar. 31, 2015USD ($)
Segment Reporting Information [Line Items]
Number of business segments | Segment			1
Goodwill	$ 32,676		$ 32,676		$ 31,534
United States
Segment Reporting Information [Line Items]
Percentage of total consolidated assets	77.00%		77.00%		77.00%
Europe
Segment Reporting Information [Line Items]
Goodwill	$ 47,900		$ 47,900		$ 46,200
International
Segment Reporting Information [Line Items]
Percentage of total consolidated assets, excluding goodwill	10.00%		10.00%		10.00%
Percentage of total product revenue	7.00%	11.00%	7.00%	11.00%