Jazz Pharmaceuticals (JAZZ) 10-K 27 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 20, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Entity Registrant Name	Jazz Pharmaceuticals plc
Entity Central Index Key	1,232,524
Trading Symbol	jazz
Entity Filer Category	Large Accelerated Filer
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		59,803,396
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 6,713,735,825

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 386,035	$ 365,963
Investments	215,000	60,000
Accounts receivable, net of allowances of $4,162 and $5,154 at December 31, 2017 and 2016, respectively	224,129	234,244
Inventories	43,245	34,051
Prepaid expenses	23,182	24,501
Other current assets	76,686	29,310
Total current assets	968,277	748,069
Property and equipment, net	170,080	107,490
Intangible assets, net	2,979,127	3,012,001
Goodwill	947,537	893,810
Deferred tax assets, net	34,559	15,060
Deferred financing costs	7,673	9,737
Other non-current assets	16,419	14,060
Total assets	5,123,672	4,800,227
Current liabilities:
Accounts payable	24,368	22,415
Accrued liabilities	198,779	193,268
Current portion of long-term debt	40,605	36,094
Income taxes payable	21,577	4,506
Deferred revenue	8,618	1,123
Total current liabilities	293,947	257,406
Deferred revenue, non-current	16,115	2,601
Long-term debt, less current portion	1,540,433	1,993,531
Deferred tax liabilities, net	383,472	556,733
Other non-current liabilities	176,608	112,617
Commitments and contingencies
Shareholders’ equity:
Ordinary shares, nominal value $0.0001 per share; 300,000 shares authorized; 59,898 and 59,820 shares issued and outstanding at December 31, 2017 and 2016, respectively	6	6
Non-voting euro deferred shares, €0.01 par value per share; 4,000 shares authorized, issued and outstanding at both December 31, 2017 and 2016	55	55
Capital redemption reserve	472	472
Additional paid-in capital	1,935,486	1,665,232
Accumulated other comprehensive loss	(140,878)	(317,333)
Retained earnings	917,956	528,907
Total shareholders’ equity	2,713,097	1,877,339
Total liabilities and shareholders’ equity	$ 5,123,672	$ 4,800,227

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) $ in Thousands	Dec. 31, 2017€ / shares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016€ / shares	Dec. 31, 2016USD ($)$ / sharesshares
Current assets:
Accounts receivable, allowances | $		$ 4,162		$ 5,154
Shareholders’ equity:
Ordinary shares, nominal value (in dollars per share) | $ / shares		$ 0.0001		$ 0.0001
Ordinary shares, authorized (in shares)		300,000,000		300,000,000
Ordinary shares, issued (in shares)		59,898,000		59,820,000
Ordinary shares, outstanding (in shares)		59,898,000		59,820,000
Nonvoting Euro Deferred shares, par value (in euros per share) | € / shares	€ 0.01		€ 0.01
Nonvoting Euro Deferred shares, authorized (in shares)		4,000,000		4,000,000
Nonvoting Euro Deferred shares, issued (in shares)		4,000,000		4,000,000
Nonvoting Euro Deferred shares, outstanding (in shares)		4,000,000		4,000,000

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Product sales, net	$ 1,601,399	$ 1,477,261	$ 1,316,819
Royalties and contract revenues	17,294	10,712	7,984
Total revenues	1,618,693	1,487,973	1,324,803
Operating expenses:
Cost of product sales (excluding amortization and impairment of intangible assets)	110,188	105,386	102,526
Selling, general and administrative	544,156	502,892	449,119
Research and development	198,442	162,297	135,253
Acquired in-process research and development	85,000	23,750	0
Intangible asset amortization	152,065	101,994	98,162
Impairment charges	0	0	31,523
Total operating expenses	1,089,851	896,319	816,583
Income from operations	528,842	591,654	508,220
Interest expense, net	(77,756)	(61,942)	(56,917)
Foreign exchange gain (loss)	(9,969)	3,372	1,445
Loss on extinguishment and modification of debt	0	(638)	(16,815)
Income before income tax provision (benefit) and equity in loss of investees	441,117	532,446	435,933
Income tax provision (benefit)	(47,740)	135,236	106,399
Equity in loss of investees	1,009	379	0
Net income	487,848	396,831	329,534
Net loss attributable to noncontrolling interests	0	0	(1)
Net income attributable to Jazz Pharmaceuticals plc	$ 487,848	$ 396,831	$ 329,535
Net income attributable to Jazz Pharmaceuticals plc per ordinary share:
Basic (in dollars per share)	$ 8.13	$ 6.56	$ 5.38
Diluted (in dollars per share)	$ 7.96	$ 6.41	$ 5.23
Weighted-average ordinary shares used in per share calculations - basic (in shares)	60,018	60,500	61,232
Weighted-average ordinary shares used in per share calculations - diluted (in shares)	61,317	61,870	63,036

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 487,848	$ 396,831	$ 329,534
Other comprehensive income (loss):
Foreign currency translation adjustments	174,973	(49,861)	(145,375)
Unrealized gain on hedging activities, net of tax expense of $212, $0 and $0, respectively	1,482	0	0
Other comprehensive income (loss)	176,455	(49,861)	(145,375)
Total comprehensive income	664,303	346,970	184,159
Comprehensive loss attributable to noncontrolling interests	0	0	(1)
Comprehensive income attributable to Jazz Pharmaceuticals plc	$ 664,303	$ 346,970	$ 184,160

Consolidated Statements of Com6

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Tax expense on hedging activities	$ 212	$ 0	$ 0

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Ordinary Shares	Non-voting Euro Deferred	Capital Redemption Reserve	Additional Paid-in Capital	Total Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Total Jazz Pharmaceuticals plc Share-holders’ Equity	Noncontrolling Interest
Beginning balance at Dec. 31, 2014	$ 1,371,208	$ 6	$ 55	$ 471	$ 1,458,005	$ (122,097)	$ 34,704	$ 1,371,144	$ 64
Beginning balance (in shares) at Dec. 31, 2014		60,643	4,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition of noncontrolling interest	(73)				(10)			(10)	(63)
Issuance of ordinary shares in conjunction with exercise of share options	32,982				32,982			32,982
Issuance of ordinary shares in conjunction with exercise of share options (in shares)		732
Issuance of ordinary shares under employee stock purchase plan	7,541				7,541			7,541
Issuance of ordinary shares under employee stock purchase plan (in shares)		75
Issuance of ordinary shares in conjunction with vesting of restricted stock units (in shares)		265
Shares withheld for payment of employee's withholding tax liability	(26,102)				(26,102)			(26,102)
Share-based compensation	91,795				91,795			91,795
Excess tax benefits from employee share options	(1,311)				(1,311)			(1,311)
Shares repurchased	(61,553)						(61,553)	(61,553)
Stock repurchased (in shares)		(410)
Other comprehensive loss	(145,375)					(145,375)		(145,375)	0
Net income	329,534						329,535	329,535	(1)
Ending balance at Dec. 31, 2015	1,598,646	$ 6	$ 55	471	1,562,900	(267,472)	302,686	$ 1,598,646	$ 0
Ending balance (in shares) at Dec. 31, 2015		61,305	4,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment from adoption of ASU No. 2016-09	107,687				0		107,687
Issuance of ordinary shares in conjunction with exercise of share options	16,880				16,880
Issuance of ordinary shares in conjunction with exercise of share options (in shares)		399
Issuance of ordinary shares under employee stock purchase plan	7,294				7,294
Issuance of ordinary shares under employee stock purchase plan (in shares)		70
Issuance of ordinary shares in conjunction with vesting of restricted stock units (in shares)		289
Shares withheld for payment of employee's withholding tax liability	(21,234)				(21,234)
Share-based compensation	99,392				99,392
Shares repurchased	(278,296)			1			(278,297)
Stock repurchased (in shares)		(2,243)
Other comprehensive loss	(49,861)					(49,861)
Net income	396,831						396,831
Ending balance at Dec. 31, 2016	1,877,339	$ 6	$ 55	472	1,665,232	(317,333)	528,907
Ending balance (in shares) at Dec. 31, 2016		59,820	4,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Exchangeable Senior Notes	149,767				149,767
Issuance of ordinary shares in conjunction with exercise of share options	22,683				22,683
Issuance of ordinary shares in conjunction with exercise of share options (in shares)		428
Issuance of ordinary shares under employee stock purchase plan	9,141				9,141
Issuance of ordinary shares under employee stock purchase plan (in shares)		104
Issuance of ordinary shares in conjunction with vesting of restricted stock units (in shares)		250
Shares withheld for payment of employee's withholding tax liability	(18,589)				(18,589)
Share-based compensation	107,252				107,252
Shares repurchased	(98,799)			0			(98,799)
Stock repurchased (in shares)		(704)
Other comprehensive loss	176,455					176,455
Net income	487,848						487,848
Ending balance at Dec. 31, 2017	$ 2,713,097	$ 6	$ 55	$ 472	$ 1,935,486	$ (140,878)	$ 917,956
Ending balance (in shares) at Dec. 31, 2017		59,898	4,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities
Net income	$ 487,848	$ 396,831	$ 329,534
Adjustments to reconcile net income to net cash provided by operating activities:
Intangible asset amortization	152,065	101,994	98,162
Share-based compensation	106,900	98,771	91,550
Impairment charges	0	0	31,523
Depreciation	13,089	11,786	9,894
Acquired in-process research and development	85,000	23,750	0
Loss on disposal of property and equipment	473	47	172
Deferred income taxes	(225,591)	(41,163)	(68,358)
Provision for losses on accounts receivable and inventory	2,190	2,209	4,062
Loss on extinguishment and modification of debt	0	638	16,815
Amortization of debt discount and deferred financing costs	30,026	22,133	22,738
Other non-cash transactions	14,321	(3,741)	(5,187)
Changes in assets and liabilities:
Accounts receivable	12,278	(25,603)	(24,841)
Inventories	(8,667)	(17,024)	6,271
Prepaid expenses and other current assets	(26,874)	(15,700)	3,720
Other long-term assets	119	267	(4,573)
Accounts payable	214	361	(2,280)
Accrued liabilities	(6,578)	11,989	2,986
Income taxes payable	16,331	2,962	(6,271)
Deferred revenue	21,009	(1,315)	(536)
Other non-current liabilities	18,934	23,199	26,562
Net cash provided by operating activities	693,087	592,391	531,943
Investing activities
Acquisition of investments	(385,000)	(132,181)	0
Proceeds from maturity of investments	230,000	66,906	0
Acquired in-process research and development	(85,000)	(23,750)	0
Purchases of property and equipment	(28,950)	(9,687)	(35,958)
Acquisitions, net of cash acquired	0	(1,502,443)	0
Acquisition of intangible assets	0	(150,000)	0
Net proceeds from sale of business	0	0	33,703
Net cash used in investing activities	(268,950)	(1,751,155)	(2,255)
Financing activities
Net proceeds from issuance of debt	559,393	994,647	898,642
Proceeds from employee equity incentive and purchase plans	31,824	24,174	40,523
Share repurchases	(98,799)	(278,296)	(61,553)
Payment of employee withholding taxes related to share-based awards	(18,589)	(21,234)	(26,102)
Repayments of long-term debt	(36,094)	(28,304)	(905,760)
Repayments under revolving credit facility	(850,000)	(150,000)	(160,000)
Proceeds from tenant improvement allowance on build-to-suit lease	3,154	0	0
Acquisition of noncontrolling interests	0	0	(73)
Net cash provided by (used in) financing activities	(409,111)	540,987	(214,323)
Effect of exchange rates on cash and cash equivalents	5,046	(5,045)	(10,622)
Net increase (decrease) in cash and cash equivalents	20,072	(622,822)	304,743
Cash and cash equivalents, at beginning of period	365,963	988,785	684,042
Cash and cash equivalents, at end of period	386,035	365,963	988,785
Supplemental disclosure of cash flow information:
Cash paid for interest	44,609	39,898	40,099
Cash paid for income taxes	174,124	160,306	145,597
Non-cash investing activities:
Amounts capitalized in connection with facility lease obligations	$ 40,970	$ 23,799	$ 4,351

Organization and Description of

Organization and Description of Business	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business Jazz Pharmaceuticals plc is an international biopharmaceutical company focused on improving patients’ lives by identifying, developing and commercializing meaningful products that address unmet medical needs. We have a diverse portfolio of products and product candidates, with a focus in the areas of sleep and hematology/oncology. Our lead marketed products are: • Xyrem ® (sodium oxybate) oral solution , the only product approved by the U.S. Food and Drug Administration, or FDA, and marketed in the U.S. for the treatment of both cataplexy and excessive daytime sleepiness, or EDS, in patients with narcolepsy; • Erwinaze ® (asparaginase Erwinia chrysanthemi ) , a treatment approved in the U.S. and in certain markets in Europe (where it is marketed as Erwinase ® ) for patients with acute lymphoblastic leukemia, or ALL, who have developed hypersensitivity to E. coli -derived asparaginase; • Defitelio ® (defibrotide sodium) , a product approved in the U.S. for the treatment of adult and pediatric patients with hepatic veno-occlusive disease, or VOD, also known as sinusoidal obstruction syndrome, or SOS, with renal or pulmonary dysfunction following hematopoietic stem cell transplantation, or HSCT, and in Europe (where it is marketed as Defitelio ® (defibrotide)) for the treatment of severe VOD in adults and children undergoing HSCT therapy; and • Vyxeos ® (daunorubicin and cytarabine) liposome for injection , a product approved in the U.S. for the treatment of adults with newly-diagnosed therapy-related acute myeloid leukemia, or t-AML, or acute myeloid leukemia, or AML, with myelodysplasia-related changes, or AML-MRC. Our strategy is to create shareholder value by: • Growing sales of the existing products in our portfolio, including by identifying and investing in growth opportunities such as new treatment indications and new geographic markets; • Acquiring or licensing rights to clinically meaningful and differentiated products on the market or product candidates at various stages of development; and • Pursuing targeted development of post-discovery differentiated product candidates. We apply a disciplined approach to allocating our resources between investments in our current commercial and development portfolio and acquisitions or in-licensing of new assets. Throughout this report, unless otherwise indicated or the context otherwise requires, all references to “Jazz Pharmaceuticals,” “the registrant,” “we,” “us,” and “our” refer to Jazz Pharmaceuticals plc and its consolidated subsidiaries. Throughout this report, all references to “ordinary shares” refer to Jazz Pharmaceuticals plc’s ordinary shares.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP, and include the accounts of Jazz Pharmaceuticals plc and our subsidiaries and intercompany transactions and balances have been eliminated. Our consolidated financial statements include the results of operations of businesses we have acquired from the date of each acquisition for the applicable reporting periods. Significant Risks and Uncertainties Our financial results are significantly influenced by sales of Xyrem. Our ability to maintain or increase Xyrem product sales is subject to a number of risks and uncertainties, including, without limitation, the potential introduction of a generic version of Xyrem before the entry dates specified in, or on terms different from those contemplated by, our settlements with companies seeking to obtain or that have obtained regulatory approval to market generic versions of Xyrem; the potential introduction of new products that compete with Xyrem; ongoing patent litigation and related proceedings; changed or increased regulatory restrictions, including with respect to the Xyrem risk evaluation and mitigation strategy, or REMS; any increase in pricing pressure from, changes in policies by, or restrictions on reimbursement imposed by, third party payors; operational disruptions at the Xyrem central pharmacy; and continued acceptance of Xyrem by physicians and patients. In addition to risks related specifically to Xyrem, we are subject to other challenges and risks specific to our business and our ability to execute on our strategy, as well as risks and uncertainties common to companies in the pharmaceutical industry with development and commercial operations, including, without limitation, risks and uncertainties associated with: effectively commercializing our other products and product candidates; pharmaceutical product development and the inherent uncertainty of clinical success; the regulatory approval process; the challenges of protecting and enhancing our intellectual property rights; our dependence on sole source suppliers for most of our products, including the risk of delays or problems in the supply or manufacture of our products and product candidates; competition; complying with applicable regulatory requirements; changes in healthcare laws and policy and related reforms; government investigations and other actions; obtaining and maintaining appropriate pricing and reimbursement for our products; business combination or product or product candidate acquisition transactions; and possible restrictions on our ability and flexibility to pursue certain future opportunities as a result of our substantial outstanding debt obligations. Business Acquisitions Our consolidated financial statements include the results of operations of an acquired business from the date of acquisition. We account for acquired businesses using the acquisition method of accounting. The acquisition method of accounting for acquired businesses requires, among other things, that assets acquired, liabilities assumed and any noncontrolling interests in the acquired business be recognized at their estimated fair values as of the acquisition date, with limited exceptions, and that the fair value of acquired in-process research and development, or IPR&D, be recorded on the balance sheet. Also, transaction costs are expensed as incurred. Any excess of the acquisition consideration over the assigned values of the net assets acquired is recorded as goodwill. Contingent consideration is included within the acquisition cost and is recognized at its fair value on the acquisition date. A liability resulting from contingent consideration is remeasured to fair value at each reporting date until the contingency is resolved and changes in fair value are recognized in earnings. Concentrations of Risk Financial instruments that potentially subject us to concentrations of credit risk consist of cash, cash equivalents, investments and derivative contracts. Our investment policy permits investments in U.S. federal government and federal agency securities, corporate bonds or commercial paper issued by U.S. corporations, money market instruments, certain qualifying money market mutual funds, certain repurchase agreements, and tax-exempt obligations of U.S. states, agencies and municipalities and places restrictions on credit ratings, maturities, and concentration by type and issuer. We are exposed to credit risk in the event of a default by the financial institutions holding our cash, cash equivalents and investments to the extent recorded on the balance sheet. We manage our foreign currency transaction risk and interest rate risk within specified guidelines through the use of derivatives. All of our derivative instruments are utilized for risk management purposes, and we do not use derivatives for speculative trading purposes. As of December 31, 2017 , we had foreign exchange forward contracts with notional amounts totaling $98.7 million . As of December 31, 2017 , the net asset fair value of outstanding foreign exchange forward contracts was $10.5 million . As of December 31, 2017 , we had interest rate swap contracts with notional amounts totaling $300.0 million . These outstanding interest rate swap contracts had a net asset fair value of $1.7 million as of December 31, 2017 . The counterparties to these contracts are large multinational commercial banks, and we believe the risk of nonperformance is not material. We are also subject to credit risk from our accounts receivable related to our product sales. We monitor our exposure within accounts receivable and record a reserve against uncollectible accounts receivable as necessary. We extend credit to pharmaceutical wholesale distributors and specialty pharmaceutical distribution companies, primarily in the U.S., and to other international distributors and hospitals. Customer creditworthiness is monitored and collateral is not required. We monitor deteriorating economic conditions in certain European countries which may result in variability of the timing of cash receipts and an increase in the average length of time that it takes to collect accounts receivable outstanding. Historically, we have not experienced significant credit losses on our accounts receivable. As of December 31, 2017 , five customers accounted for 90% of gross accounts receivable including Express Scripts Specialty Distribution Services, Inc. and its affiliates, or Express Scripts, which accounted for 71% of gross accounts receivable, and McKesson Corporation and affiliates, or McKesson, which accounted for 15% of gross accounts receivable. As of December 31, 2016 , five customers accounted for 90% of gross accounts receivable including Express Scripts, which accounted for 73% of gross accounts receivable, and McKesson, which accounted for 13% of gross accounts receivable. We depend on single source suppliers for most of our products, product candidates and their active pharmaceutical ingredients, or APIs. With respect to Xyrem, the API is manufactured for us by a single source supplier and the finished product is manufactured both by us in our facility in Athlone, Ireland and by our U.S.-based Xyrem supplier. Cash Equivalents and Investments We consider all highly liquid investments, readily convertible to cash, that mature within three months or less from date of purchase to be cash equivalents. Investments consist of time deposits with initial maturities of greater than three months. Collectively, cash equivalents and investments are considered available-for-sale and are recorded at fair value. Unrealized gains and losses, net of tax, are recorded in accumulated other comprehensive loss in shareholders’ equity. We use the specific-identification method for calculating realized gains and losses on securities sold. Realized gains and losses and declines in value judged to be other than temporary on investments are included in interest expense, net in the consolidated statements of income. Derivative Instruments and Hedging Activities We record the fair value of derivative instruments as either assets or liabilities on the consolidated balance sheets. Changes in the fair value of derivative instruments are recorded each period in current earnings or other comprehensive income (loss), depending on whether a derivative instrument is designated as part of a hedging transaction and, if it is, the type of hedging transaction. For a derivative to qualify as a hedge at inception and throughout the hedged period, we formally document the nature and relationships between the hedging instruments and hedged item. We assess, both at inception and on an on-going basis, whether the derivative instruments that are used in cash flow hedging transactions are highly effective in offsetting the changes in cash flows of hedged items. We assess hedge ineffectiveness on a quarterly basis and record the gain or loss related to the ineffective portion of derivative instruments, if any, to current earnings. If we determine that a forecasted transaction is no longer probable of occurring, we discontinue hedge accounting and any related unrealized gain or loss on the derivative instrument is recognized in current earnings. Derivatives that are not designated and do not qualify as hedges are adjusted to fair value through current earnings. Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method for all inventories. Our policy is to write down inventory that has become obsolete, inventory that has a cost basis in excess of its expected net realizable value and inventory in excess of expected requirements. The estimate of excess quantities is subjective and primarily dependent on our estimates of future demand for a particular product. If our estimate of future demand changes, we consider the impact on the reserve for excess inventory and adjust the reserve as required. Increases in the reserve are recorded as charges in cost of product sales. For product candidates that have not been approved by the FDA, inventory used in clinical trials is expensed at the time of production and recorded as research and development expense. For products that have been approved by the FDA, inventory used in clinical trials is expensed at the time the inventory is packaged for the clinical trial. Prior to receiving FDA approval, costs related to purchases of the API and the manufacturing of the product candidate are recorded as research and development expense. All direct manufacturing costs incurred after approval are capitalized into inventory. Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Estimated useful lives are as follows: Buildings 40 years Manufacturing equipment and machinery 5-10 years Computer software and equipment 3 years Furniture and fixtures 5 years Leasehold improvements and the build-to-suit facility are amortized over the shorter of the noncancelable term of our leases or their economic useful lives. Maintenance and repairs are expensed as incurred. Operating Leases and Financing Obligations We recognize rent expense under operating leases on a straight-line basis over the term of the lease with the difference between the expense and cash payments recorded as deferred rent on the consolidated balance sheets. For certain build-to-suit lease arrangements where we have concluded that we are the “deemed owner” of the building, for accounting purposes only, during the construction period, we are required to record an asset with a corresponding financing obligation for the construction costs incurred by the landlord. The financing obligation is recorded as a component of other non-current liabilities in the consolidated balance sheets. We increase the asset and financing obligation as additional building costs are incurred by the landlord during the construction period. Once construction is complete, we evaluate whether the asset qualifies for sale-leaseback accounting treatment. If the lease meets the sale-leaseback criteria, we remove the asset and the related liability from the consolidated balance sheets and treat the lease as either an operating or capital lease based on an assessment of the accounting guidance. If the arrangement does not qualify for sale-leaseback treatment, we reduce the financing obligation over the lease term as payments are made and depreciate the asset over its estimated useful life or lease term, whichever is shorter. Future lease payments associated with build-to-suit leases where we are the deemed owner are allocated between the land and building components. The portion of the lease payments allocated to the land is treated for accounting purposes as operating lease payments, and therefore is recorded as rent expense in the consolidated statements of income. The portion of the lease payments allocated to the building is further bifurcated into a portion allocated to interest expense and a portion allocated to reduce the build-to-suit financing obligation. Goodwill Goodwill represents the excess of the acquisition consideration over the fair value of assets acquired and liabilities assumed. We have determined that we operate in a single segment and have a single reporting unit associated with the development and commercialization of pharmaceutical products. The annual test for goodwill impairment is a two-step process. The first step is a comparison of the fair value of the reporting unit with its carrying amount, including goodwill. If this step indicates impairment, then, in the second step, the loss is measured as the excess of recorded goodwill over its implied fair value. Implied fair value is the excess of the fair value of the reporting unit over the fair value of all identified assets and liabilities. We test goodwill for impairment annually in October and when events or changes in circumstances indicate that the carrying value may not be recoverable. Acquired In-Process Research and Development The initial costs of rights to IPR&D projects acquired in an asset acquisition are expensed as IPR&D unless the project has an alternative future use. The fair value of IPR&D projects acquired in a business combination are capitalized and accounted for as indefinite-lived intangible assets until the underlying project receives regulatory approval, at which point the intangible asset will be accounted for as a finite-lived intangible asset, or discontinued, at which point the intangible asset will be written off. Development costs incurred after an acquisition are expensed as incurred. Intangible Assets Intangible assets with finite useful lives consist primarily of purchased developed technology and are amortized on a straight-line basis over their estimated useful lives, which range from two to 18 years. The estimated useful lives associated with finite-lived intangible assets are consistent with the estimated lives of the associated products and may be modified when circumstances warrant. Such assets are reviewed for impairment when events or circumstances indicate that the carrying value of an asset may not be recoverable. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset and its eventual disposition are less than its carrying amount. The amount of any impairment is measured as the difference between the carrying amount and the fair value of the impaired asset. Revenue Recognition Revenues are recognized when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed and determinable and collection is reasonably assured. Product Sales, Net Product sales revenue is recognized when title has transferred to the customer and the customer has assumed the risks and rewards of ownership, which is typically on delivery to the customer or, in the case of products that are subject to consignment agreements, when the customer removes product from our consigned inventory location for shipment directly to a patient. Revenue from sales transactions where the buyer has the right to return the product is recognized at the time of sale only if (i) the seller’s price to the buyer is substantially fixed or determinable at the date of sale, (ii) the buyer has paid the seller, or the buyer is obligated to pay the seller and the obligation is not contingent on resale of the product, (iii) the buyer’s obligation to the seller would not be changed in the event of theft or physical destruction or damage of the product, (iv) the buyer acquiring the product for resale has economic substance apart from that provided by the seller, (v) the seller does not have significant obligations for future performance to directly bring about resale of the product by the buyer, and (vi) the amount of future returns can be reasonably estimated. Revenues from sales of products are recorded net of estimated allowances for returns, specialty distributor fees, wholesaler fees, prompt payment discounts, government rebates, government chargebacks, coupon programs and rebates under managed care plans. Provisions for returns, specialty distributor fees, wholesaler fees, government rebates, coupon programs and rebates under managed care plans are included within current liabilities in our consolidated balance sheets. Provisions for government chargebacks and prompt payment discounts are generally shown as a reduction in accounts receivable. Calculating certain of these items involves estimates and judgments based on sales or invoice data, contractual terms, historical utilization rates, new information regarding changes in these programs’ regulations and guidelines that would impact the amount of the actual rebates, our expectations regarding future utilization rates for these programs and channel inventory data. Adjustments to estimates for these allowances have not been material. Royalties and Contract Revenues We receive royalties from third parties based on sales of our products under licensing and distribution arrangements. For those arrangements where royalties are reasonably estimable, we recognize revenues based on estimates of royalties earned during the applicable period, and adjust for differences between the estimated and actual royalties in the following quarter. Historically, these adjustments have not been significant. Our contract revenues consist of fees and milestone payments. Non-refundable fees where we have no continuing performance obligations are recognized as revenues when there is persuasive evidence of an arrangement and collection is reasonably assured. In situations where we have continuing performance obligations, non-refundable fees are deferred and are recognized ratably over our projected performance period. We recognize at-risk milestone payments, which are typically related to regulatory, commercial or other achievements by us or our licensees and distributors, as revenues when the milestone is accomplished and collection is reasonably assured. Sales-based milestone payments are typically payments made to us that are triggered when aggregate net sales of a product by a collaborator for a specified period (for example, an annual period) reach an agreed upon threshold amount. We recognize sales-based milestone payments from a collaborator when the event which triggers the obligation of payment has occurred, there is no further obligation on our part in connection with the payment, and collection is reasonably assured. Refundable fees are deferred and recognized as revenues upon the later of when they become nonrefundable or when our performance obligations are completed. Cost of Product Sales Cost of product sales includes manufacturing and distribution costs, the cost of drug substance, royalties due to third parties on product sales, product liability and cargo insurance, FDA user fees, freight, shipping, handling and storage costs and salaries and related costs of employees involved with production. Excluded from cost of product sales shown on the consolidated statements of income is amortization of acquired developed technology of $149.1 million , $99.0 million and $93.0 million in 2017 , 2016 and 2015 , respectively. Research and Development Research and development expenses consist primarily of costs related to clinical studies and outside services, personnel expenses and other research and development costs, including milestone payments incurred prior to regulatory approval of products. Clinical study and outside services costs relate primarily to services performed by clinical research organizations, clinical studies performed at clinical sites, materials and supplies, and other third party fees. Personnel expenses relate primarily to salaries, benefits and share-based compensation. Other research and development expenses primarily include overhead allocations consisting of various support and facilities-related costs. Research and development costs are expensed as incurred. For product candidates that have not been approved by the FDA, inventory used in clinical trials is expensed at the time of production and recorded as research and development expense. For products that have been approved by the FDA, inventory used in clinical trials is expensed at the time the inventory is packaged for the trial. Advertising Expenses We expense the costs of advertising, including promotional expenses, as incurred. Advertising expenses were $36.6 million , $29.5 million and $27.9 million in 2017 , 2016 and 2015 , respectively. Income Taxes We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between the financial statement carrying amount and the tax basis of assets and liabilities and are measured using enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is provided when it is more-likely-than-not that some portion or all of a deferred tax asset will not be realized. We recognize the benefits of a tax position if it is “more-likely-than-not” of being sustained. A recognized tax benefit is then measured at the largest amount of benefit that is greater than fifty percent likely of being realized upon settlement. Interest and penalties related to unrecognized tax benefits are included in the income tax provision and classified with the related liability on the consolidated balance sheets. Foreign Currency Our functional and reporting currency is the U.S. dollar. The assets and liabilities of our subsidiaries that have a functional currency other than the U.S. dollar are translated into U.S. dollars at the exchange rate prevailing at the balance sheet date with the results of operations of subsidiaries translated at the average exchange rate for the reporting period. The cumulative foreign currency translation adjustment is recorded as a component of accumulated other comprehensive income (loss) in shareholders’ equity. Transactions in foreign currencies are translated into the functional currency of the relevant subsidiary at the rate of exchange prevailing at the date of the transaction. Any monetary assets and liabilities arising from these transactions are translated into the relevant functional currency at exchange rates prevailing at the balance sheet date or on settlement. Resulting gains and losses are recorded in foreign exchange gain (loss) in our consolidated statements of income. Deferred Financing Costs Deferred financing costs are reported at cost, less accumulated amortization and are presented in the consolidated balance sheets as a direct deduction from the carrying value of the associated debt, with the exception of deferred financing costs associated with revolving-debt arrangements which are presented as assets. The related amortization expense is included in interest expense, net in our consolidated statements of income. Contingencies From time to time, we may become involved in claims and other legal matters arising in the ordinary course of business. We record accruals for loss contingencies to the extent that we conclude that it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. Legal fees and other expenses related to litigation are expensed as incurred and included in selling, general and administrative expenses. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures in the consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. Actual results could differ materially from those estimates. Net Income per Ordinary Share Basic net income per ordinary share attributable to Jazz Pharmaceuticals plc is based on the weighted-average number of ordinary shares outstanding. Diluted net income per ordinary share attributable to Jazz Pharmaceuticals plc is based on the weighted-average number of ordinary shares outstanding and potentially dilutive ordinary shares outstanding. Basic and diluted net income per ordinary share attributable to Jazz Pharmaceuticals plc were computed as follows (in thousands, except per share amounts): Year Ended December 31, 2017 2016 2015 Numerator: Net income attributable to Jazz Pharmaceuticals plc $ 487,848 $ 396,831 $ 329,535 Denominator: Weighted-average ordinary shares used in per share calculations - basic 60,018 60,500 61,232 Dilutive effect of employee equity incentive and purchase plans 1,299 1,370 1,804 Weighted-average ordinary shares used in per share calculations - diluted 61,317 61,870 63,036 Net income per ordinary share : Basic $ 8.13 $ 6.56 $ 5.38 Diluted $ 7.96 $ 6.41 $ 5.23 Potentially dilutive ordinary shares from our employee equity incentive and purchase plans, our 1.875% exchangeable senior notes due 2021, or the 2021 Notes, and our 1.50% exchangeable senior notes due 2024, or the 2024 Notes, are determined by applying the treasury stock method to the assumed exercise of share options and warrants, the assumed vesting of outstanding restricted stock units, or RSUs, the assumed issuance of ordinary shares under our employee stock purchase plan, or ESPP, and the assumed issuance of ordinary shares upon exchange of the 2021 Notes and the 2024 Notes, which we refer to together as the Exchangeable Senior Notes. The potential issue of ordinary shares issuable upon exchange of the Exchangeable Senior Notes had no effect on diluted net income per ordinary share because the average price of our ordinary shares in 2017 , 2016 and 2015 did not exceed the effective exchange prices per ordinary share of the Exchangeable Senior Notes. The following table represents the weighted-average ordinary shares that were excluded from the computation of diluted net income attributable to Jazz Pharmaceuticals plc per ordinary share for the years presented because including them would have an anti-dilutive effect (in thousands): Year Ended December 31, 2017 2016 2015 Exchangeable Senior Notes 3,805 2,878 2,878 Options to purchase ordinary shares and RSUs 3,319 3,010 1,609 Ordinary shares under ESPP 14 93 — Share-Based Compensation We account for compensation cost for all share-based awards at fair value on the date of grant. The fair value is recognized as expense over the service period, net of estimated forfeitures, using the straight-line method. The estimation of share-based awards that will ultimately vest requires judgment, and, to the extent actual results or updated estimates differ from current estimates, such amounts will be recorded as a cumulative adjustment in the period estimates are revised. We primarily consider historical experience when estimating expected forfeitures. Recent Accounting Pronouncements In August 2017, the Financial Accounting Standards Board, or FASB, issued ASU No. 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities”. ASU No. 2017-12 amends and simplifies existing guidance in order to allow companies to more accurately present the economic effects of risk management activities in their financial statements. ASU No. 2017-12 is effective for reporting periods beginning after December 15, 2018, with early adoption permitted. We have elected to early adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In January 2017, the FASB, issued ASU No. 2017-04, “Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” which simplifies the accounting for goodwill impairment by eliminating Step 2 of the current goodwill impairment test. Goodwill impairment will now be the amount by which the reporting unit’s carrying value exceeds its fair value, limited to the carrying value of the goodwill. The standard is effective for us beginning January 1, 2020. Early adoption is permitted for any impairment tests performed after January 1, 2017. The new guidance is not expected to have a material impact on our consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” which provides clarification on the definition of a business and adds guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018. The future impact of ASU No. 2017-01 will be dependent upon the nature of our future acquisition or disposition transactions, if any. In October 2016, the FASB issued ASU No. 2016-16, “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory” which requires an entity to recognize the income tax consequences of an intra-entity asset transfer, other than an intra-entity asset transfer of inventory, when the transfer occurs. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments”. ASU 2016-15 addresses how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842)”. Under the new guidance, lessees will be required to recognize a right-of-use asset, which represents the lessee’s right to use, or control the use of, a specified asset for the lease term, and a corresponding lease liability, which represents the lessee’s obligation to make lease payments under a lease, measured on a discounted basis. ASU No. 2016-02 is effective beginning January 1, 2019 and early adoption is permitted. ASU No. 2016-02 must be adopted on a modified retrospective transition basis for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the consolidated financial statements. The adoption of ASU No. 2016-02 will result in a significant increase in our consolidated balance sheet for right-of-use assets and lease liabilities. While we are continuing to assess all potential impacts of the standard, we currently believe the most significant impact relates to our accounting for the lease agreements we entered into in January 2015 and September 2017 to lease office space located in Palo Alto, California in buildings constructed or to be constructed by the landlord, which are accounted for as build-to-suit arrangements under existing accounting standards, and t

Business Combination, Asset Acq

Business Combination, Asset Acquisitions, and Disposition	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Business Combination, Asset Acquisitions, and Disposition	Business Combination, Asset Acquisitions and Disposition Celator Acquisition On May 27, 2016, we entered into a definitive merger agreement with Celator Pharmaceuticals Inc., or Celator, pursuant to which we made a cash tender offer of $30.25 per share for all of the outstanding shares of Celator’s common stock. As of the expiration of the offer period on July 12, 2016, 36,516,173 shares, which represented approximately 81% of Celator’s then outstanding common stock, were properly tendered and not withdrawn in the tender offer. The condition to the tender offer that more than 50% of Celator’s outstanding common stock be validly tendered and not withdrawn prior to the expiration of the tender offer was satisfied. In addition, notices of guaranteed delivery were delivered with respect to 2,016,237 additional shares, representing approximately 4% of Celator’s outstanding common stock as of the expiration of the tender offer. On July 12, 2016, we completed the acquisition of Celator, or the Celator Acquisition, under the terms of the merger agreement, pursuant to which Celator became an indirect wholly owned subsidiary of Jazz Pharmaceuticals plc and each share of Celator common stock then outstanding (other than shares owned by us or Celator) was converted into the right to receive $30.25 , the same price per share offered in the tender offer. The aggregate cash consideration for the Celator Acquisition was $1.5 billion . On July 12, 2016, we entered into the amended credit agreement that provides for a revolving credit facility of $1.25 billion , which replaced our prior revolving credit facility of $750.0 million , and a $750.0 million term loan facility. Please see Note 11 for further information regarding the 2015 credit agreement and the amended credit agreement. We used the proceeds of $1.0 billion of loans under the revolving credit facility, together with cash on hand, to fund the Celator Acquisition. Celator was an oncology-focused biopharmaceutical company seeking to transform the science of combination therapy and develop products to improve patient outcomes in cancer. The Celator Acquisition broadened our hematology/oncology portfolio with the acquisition of worldwide development and commercialization rights to Vyxeos. In addition, the Celator Acquisition provided us with Celator’s proprietary technology platform, CombiPlex, which enables the rational design and rapid evaluation of optimized combinations of additional anti-cancer drugs. The Celator Acquisition was accounted for as a business combination using the acquisition method under which assets and liabilities of Celator were recorded at their respective estimated fair values as of the closing date of the Celator Acquisition and added to the assets and liabilities of Jazz Pharmaceuticals plc, including an amount for goodwill representing the difference between the acquisition consideration and the estimated fair value of the identifiable net assets. The results of operations of Celator and the estimated fair values of the assets acquired and liabilities assumed have been included in our consolidated financial statements since the closing date of the Celator Acquisition. In 2016, we incurred $10.0 million in acquisition-related costs related to the Celator Acquisition, which primarily consisted of banking, legal, accounting and valuation-related expenses. These expenses were recorded in selling, general and administrative expense in the accompanying consolidated statements of income. We did not recognize any revenues from the acquired Celator business in 2016. In 2017, we recognized revenue from the acquired Celator business of $33.8 million following the launch of Vyxeos in August 2017. The portion of total expenses and net loss associated with the acquired Celator business was not separately identifiable due to the integration with our operations. The fair values of assets acquired and liabilities assumed at the closing date of the Celator Acquisition are summarized below (in thousands): Cash and cash equivalents $ 26,137 Other receivables 386 Prepaid expenses and deposits 151 Property and equipment 767 Intangible assets 1,811,250 Goodwill 252,825 Other non-current assets 43 Accrued liabilities (19,076 ) Deferred tax liability, net, non-current (542,901 ) Other non-current liabilities (1,002 ) Total acquisition consideration - cash paid $ 1,528,580 Identifiable intangible assets acquired comprised IPR&D, which represented incomplete research and development projects at Celator related to Vyxeos. Management estimated the fair value of Vyxeos IPR&D to be approximately $1.8 billion . The fair value of acquired IPR&D was determined using the income approach, including the application of probability factors related to the likelihood of success of Vyxeos reaching final development and commercialization. This approach also took into consideration information and certain program-related documents and forecasts prepared by management. The fair value of acquired IPR&D was capitalized as of the closing date of the Celator Acquisition. After receiving FDA approval of our new drug application, or NDA, for Vyxeos in August 2017, we reclassified the IPR&D balance of $1.8 billion from an indefinite-lived intangible asset to an acquired developed technology finite-lived intangible asset. This acquired developed technology asset is being amortized over its estimated useful life of 18 years. The excess of the total acquisition consideration over the fair value amounts assigned to the assets acquired and the liabilities assumed represents the goodwill amount resulting from the Celator Acquisition. We believe that the factors that contributed to goodwill included the Celator workforce, which will complement our clinical experience in hematology/oncology and our expertise in reaching targeted physicians who treat serious medical conditions, and the deferred tax consequences of intangible assets recorded for financial statement purposes. We do not expect any portion of this goodwill to be deductible for tax purposes. Pro Forma Financial Information (Unaudited) The following unaudited supplemental pro forma information presents our combined historical results of operations with pro forma adjustments as if the Celator Acquisition had been completed on January 1, 2015. The primary pro forma adjustments include: • The exclusion of acquisition-related and integration expenses of $13.6 million in 2016 and the inclusion of these expenses in 2015. • An increase in interest expense of $13.7 million in 2016 and $25.9 million in 2015 incurred on additional borrowings made to partially fund the Celator Acquisition as if the borrowings had occurred on January 1, 2015. The unaudited pro forma results do not assume any operating efficiencies as a result of the consolidation of operations and are as follows (in thousands, except per share data): Year Ended December 31, 2016 2015 Revenues $ 1,488,118 $ 1,326,246 Net income attributable to Jazz Pharmaceuticals plc $ 386,342 $ 283,113 Net income attributable to Jazz Pharmaceuticals plc per ordinary share - basic $ 6.39 $ 4.62 Net income attributable to Jazz Pharmaceuticals plc per ordinary share - diluted $ 6.24 $ 4.49 Collaboration and Option Agreement In August 2017, we entered into a collaboration and option agreement with ImmunoGen, Inc., or ImmunoGen, granting us rights to opt into exclusive, worldwide licenses to develop and commercialize two early-stage, hematology-related antibody-drug conjugate, or ADC, programs, as well as an additional program to be designated during the term of the agreement. The programs covered under the agreement include IMGN779, a CD33-targeted ADC for the treatment of AML in Phase 1 testing, and IMGN632, a CD123-targeted ADC for hematological malignancies expected to enter clinical testing before the end of 2017. Under the terms of the agreement, ImmunoGen will be responsible for the development of the three ADC programs prior to any potential opt-in by us. Following any opt-in, we would be responsible for any further development as well as for potential regulatory submissions and commercialization. As part of the agreement, we paid ImmunoGen a non-refundable upfront payment of $75.0 million , which was charged to acquired IPR&D expense upon closing of the transaction. Additionally, we will pay ImmunoGen up to $100 million in development funding over seven years to support the three ADC programs. For each program, we may exercise our opt-in right at any time prior to a pivotal study or any time prior to a biologics license application upon payment of an option exercise fee. The option exercise fee depends on the timing of exercise and certain other conditions. For each program to which we elect to opt-in, ImmunoGen would be eligible to receive milestone payments based on receiving regulatory approval of the applicable product, plus tiered royalties as a percentage of commercial sales. After opt-in, we will share with ImmunoGen the costs associated with developing and obtaining regulatory approvals of the applicable product in the U.S. and the European Union, or EU. ImmunoGen has the right to co-commercialize one product (or two products, under certain limited circumstances) with us in the U.S. with U.S. profit-sharing in lieu of our payment of applicable U.S. milestone and royalties to ImmunoGen. License and Option Agreement In July 2016, we entered into an agreement with Pfenex Inc., or Pfenex, that granted us worldwide rights to develop and commercialize multiple early-stage hematology product candidates and an option for us to negotiate a license for a recombinant pegaspargase product candidate. This agreement was amended in December 2017. Under the amended agreement, Pfenex received upfront, option and development milestone payments totaling $35.3 million and may be eligible to receive additional payments of up to $189 million based on the achievement of certain development, regulatory and sales milestones. In 2017, we recognized expense of $19.5 million within research and development expenses. In 2016, we recognized expenses of $15.8 million , of which $15.0 million was charged to acquired IPR&D expense upon closing of the transaction and $0.8 million was charged to research and development expenses. Acquisition of Alizé Pharma II S.A.S. In March 2016, we acquired all of the outstanding shares of Alizé Pharma II S.A.S., a privately held biotechnology company, for an upfront payment of $8.8 million . In connection with the acquisition, we obtained intellectual property and know-how related to recombinant crisantaspase. The transaction includes contingent regulatory milestone payments of up to € 10 million . The transaction was accounted for as an asset acquisition and the upfront payment was charged to acquired IPR&D expense upon closing of the transaction. Disposition In March 2015, we sold certain products and the related business that we originally acquired as part of our June 2012 acquisition of EUSA Pharma Inc., or the EUSA Acquisition. The purchase price for the products and related business was $34.0 million , subject to pre- and post-closing purchase price adjustments. In 2015, we recognized a loss on disposal of $0.2 million within selling, general and administrative expenses in our consolidated statements of income. The related assets met the assets held for sale criteria and were reclassified to assets held for sale as of December 31, 2014. Goodwill was allocated to these assets using the relative fair value method. We have determined that the disposition of these assets did not qualify for reporting as a discontinued operation, because the sale did not represent a strategic shift that had or will have a major effect on our operations and financial results.

Cash and Available-for-Sale Sec

Cash and Available-for-Sale Securities	12 Months Ended
	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Cash and Available-for-Sale Securities	Cash and Available-for-Sale Securities Cash and cash equivalents and investments consisted of the following (in thousands): December 31, 2017 Amortized Gross Gross Estimated Cash and Cash Equivalents Investments Cash $ 225,235 $ — $ — $ 225,235 $ 225,235 $ — Time deposits 235,000 — — 235,000 20,000 215,000 Money market funds 140,800 — — 140,800 140,800 — Totals $ 601,035 $ — $ — $ 601,035 $ 386,035 $ 215,000 December 31, 2016 Amortized Gross Gross Estimated Cash and Cash Investments Cash $ 215,963 $ — $ — $ 215,963 $ 215,963 $ — Time deposits 210,000 — — 210,000 150,000 60,000 Totals $ 425,963 $ — $ — $ 425,963 $ 365,963 $ 60,000 Cash equivalents and investments are considered available-for-sale securities. We use the specific-identification method for calculating realized gains and losses on securities sold and include them in interest expense, net in the consolidated statements of income. Our investment balances represent time deposits with original maturities of greater than three months and less than one year.

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement The following table summarizes, by major security type, our available-for-sale securities and derivative contracts that were measured at fair value on a recurring basis and were categorized using the fair value hierarchy (in thousands): December 31, 2017 December 31, 2016 Quoted Significant Total Significant Total Assets: Available-for-sale securities: Time deposits $ — $ 235,000 $ 235,000 $ 210,000 $ 210,000 Money market funds 140,800 — 140,800 — — Interest rate contracts — 2,138 2,138 — — Foreign exchange forward contracts — 15,495 15,495 — — Totals $ 140,800 $ 252,633 $ 393,433 $ 210,000 $ 210,000 Liabilities: Interest rate contracts $ — $ 392 $ 392 $ — $ — Foreign exchange forward contracts — 5,017 5,017 — — Totals $ — $ 5,409 $ 5,409 $ — $ — As of December 31, 2017 , our available-for-sale securities included time deposits and money market funds and their carrying values were approximately equal to their fair values. Time deposits were measured at fair value using Level 2 inputs and money market funds were measured using quoted prices in active markets, which represent Level 1 inputs. Level 2 inputs, obtained from various third party data providers, represent quoted prices for similar assets in active markets, or these inputs were derived from observable market data, or if not directly observable, were derived from or corroborated by other observable market data. Our derivative assets and liabilities include interest rate and foreign exchange derivatives that are measured at fair value using observable market inputs such as forward rates, interest rates, our own credit risk as well as an evaluation of our counterparties’ credit risks. Based on these inputs, the derivative assets and liabilities are classified within Level 2 of the fair value hierarchy. There were no transfers between the different levels of the fair value hierarchy in 2017 or in 2016 . As of December 31, 2017 , the estimated fair values of the 2021 Notes and the 2024 Notes, were approximately $577 million and $543 million , respectively. The fair values of the Exchangeable Senior Notes were estimated using quoted market prices obtained from brokers (Level 2). The estimated fair value of our borrowings under our term loan was approximately equal to its book value based on the borrowing rates currently available for variable rate loans (Level 2).

Derivatives and Hedging Activit

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivative Instruments and Hedging Activities We are exposed to certain risks arising from operating internationally, including fluctuations in interest rates on our outstanding term loan borrowings and fluctuations in foreign exchange rates primarily related to the translation of euro-denominated net monetary liabilities, including intercompany balances, held by subsidiaries with a U.S. dollar functional currency. We manage these exposures within specified guidelines through the use of derivatives. All of our derivative instruments are utilized for risk management purposes, and we do not use derivatives for speculative trading purposes. To achieve a desired mix of floating and fixed interest rates on our variable rate debt, we entered into interest rate swap agreements in March 2017 which are effective from March 3, 2017 until July 12, 2021. These agreements hedge contractual term loan interest rates. As of December 31, 2017 , the interest rate swap agreements had a notional amount of $300.0 million . As a result of these agreements, the interest rate on a portion of our term loan borrowings was fixed at 1.895% , plus the borrowing spread, until July 12, 2021. The effective portion of changes in the fair value of derivatives designated as and that qualify as cash flow hedges is recorded in accumulated other comprehensive loss and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The ineffective portion of the change in fair value is recognized directly in earnings. The impact on accumulated other comprehensive loss and earnings from derivative instruments that qualified as cash flow hedges was as follows (in thousands): Year Ended December 31, 2017 2016 Loss recognized in accumulated other comprehensive loss, net of tax $ (213 ) $ — Loss reclassified from accumulated other comprehensive loss to interest expense, net of tax $ 1,695 $ — A ssuming no change in LIBOR-based interest rates from market rates as of December 31, 2017 , $0.4 million of losses recognized in accumulated other comprehensive loss will be reclassified to earnings over the next 12 months. The gain related to the ineffective portion of derivative instruments that qualified as cash flow hedges for the twelve months ended December 31, 2017 was $0.1 million . We enter into foreign exchange forward contracts, with durations of up to 365 days, designed to limit the exposure to fluctuations in foreign exchange rates related to the translation of certain non-U.S. dollar denominated liabilities, including intercompany balances. Hedge accounting is not applied to these derivative instruments as gains and losses on these hedge transactions are designed to offset gains and losses on underlying balance sheet exposures. As of December 31, 2017 , the notional amount of foreign exchange contracts where hedge accounting is not applied was $98.7 million . The foreign exchange gain (loss) in our consolidated statements of income included gains of $10.5 million associated with foreign exchange contracts not designated as hedging instruments in 2017 . We did not enter into foreign exchange forward contracts in 2016 and 2015 . The cash flow effects of our derivative contracts are included within net cash provided by operating activities in the consolidated statements of cash flows. The following table summarizes the fair value of outstanding derivatives as of December 31, 2017 (in thousands): December 31, 2017 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments: Interest rate contracts Other non-current assets $ 2,138 Accrued liabilities $ 392 Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets 15,495 Accrued liabilities 5,017 Total fair value of derivative instruments $ 17,633 $ 5,409 Although we do not offset derivative assets and liabilities within our consolidated balance sheets, our International Swap and Derivatives Association agreements provide for net settlement of transactions that are due to or from the same counterparty upon early termination of the agreement due to an event of default or other termination event. The following table summarizes the potential effect on our consolidated balance sheets of offsetting our interest rate contracts and foreign exchange forward contracts subject to such provisions (in thousands): December 31, 2017 Gross Amounts of Recognized Assets/Liabilities Gross Amounts Offset in the Consolidated Balance Sheet Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Description Derivative Financial Instruments Cash Collateral Received (Pledged) Net Amount Derivative assets $ 1,639 $ — $ 1,639 $ (875 ) $ — $ 764 Derivative liabilities $ (875 ) $ — $ (875 ) $ 875 $ — $ — There were no outstanding derivatives as of December 31, 2016 .

Inventories

Inventories	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of the following (in thousands): December 31, 2017 2016 Raw materials $ 3,542 $ 1,547 Work in process 15,692 18,689 Finished goods 24,011 13,815 Total inventories $ 43,245 $ 34,051

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment Property and equipment consisted of the following (in thousands): December 31, 2017 2016 Build-to-suit facility $ 51,721 $ — Land and buildings 46,729 46,033 Leasehold improvements 28,779 9,328 Manufacturing equipment and machinery 23,586 19,596 Construction-in-progress 21,738 33,427 Computer software 19,969 17,832 Computer equipment 12,814 10,980 Furniture and fixtures 5,947 2,436 Subtotal 211,283 139,632 Less accumulated depreciation and amortization (41,203 ) (32,142 ) Property and equipment, net $ 170,080 $ 107,490 Depreciation and amortization expense (including amortization expense related to a facility lease) on property and equipment amounted to $13.1 million , $11.8 million and $9.9 million for the years ended December 31, 2017, 2016 and 2015, respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets The gross carrying amount of goodwill was as follows (in thousands): Balance at December 31, 2016 $ 893,810 Foreign exchange 53,727 Balance at December 31, 2017 $ 947,537 The gross carrying amounts and net book values of our intangible assets were as follows (in thousands): December 31, 2017 December 31, 2016 Remaining Gross Accumulated Net Book Gross Accumulated Net Book Acquired developed technologies 14.9 $ 3,392,832 $ (562,473 ) $ 2,830,359 $ 1,477,618 $ (410,523 ) $ 1,067,095 Manufacturing contracts 0.1 12,824 (12,634 ) 190 11,278 (8,292 ) 2,986 Trademarks — 2,910 (2,910 ) — 2,872 (2,872 ) — Total finite-lived intangible assets 3,408,566 (578,017 ) 2,830,549 1,491,768 (421,687 ) 1,070,081 Acquired IPR&D assets 148,578 — 148,578 1,941,920 — 1,941,920 Total intangible assets $ 3,557,144 $ (578,017 ) $ 2,979,127 $ 3,433,688 $ (421,687 ) $ 3,012,001 The increase in the gross carrying amount of intangible assets as of December 31, 2017 compared to December 31, 2016 reflected the positive impact of foreign currency translation adjustments, which was due to the strengthening of the euro against the U.S. dollar. Additionally, after receiving FDA approval of our NDA for Vyxeos in August 2017, we reclassified $1.8 billion of acquired IPR&D from an indefinite-lived intangible asset to an acquired developed technology finite-lived intangible asset. This acquired developed technology asset is being amortized over its estimated useful life of 18 years. The assumptions and estimates used to determine future cash flows and remaining useful lives of our intangible and other long-lived assets are complex and subjective. They can be affected by various factors, including external factors, such as industry and economic trends, and internal factors such as changes in our business strategy and our forecasts for specific product lines. As a result of our decision to terminate a pivotal Phase 2 clinical trial of JZP-416, we recognized an impairment charge of $31.5 million to our acquired IPR&D asset in 2015. Based on finite-lived intangible assets recorded as of December 31, 2017 , and assuming the underlying assets will not be impaired and that we will not change the expected lives of the assets, future amortization expenses were estimated as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2018 $ 209,912 2019 209,674 2020 206,706 2021 205,655 2022 204,922 Thereafter 1,793,680 Total $ 2,830,549

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consisted of the following (in thousands): December 31, 2017 2016 Rebates and other sales deductions $ 81,368 $ 72,344 Employee compensation and benefits 54,930 43,363 Royalties 8,058 11,643 Accrued interest 7,297 5,179 Derivative instrument liabilities 5,409 — Sales returns reserve 3,651 4,366 Professional fees 3,213 4,596 Selling and marketing accruals 3,189 3,924 Inventory-related accruals 3,002 3,350 Accrued construction-in-progress 2,827 1,597 Clinical trial accruals 2,181 10,139 Accrued contract termination fees — 11,612 Other 23,654 21,155 Total accrued liabilities $ 198,779 $ 193,268

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	Debt The following table summarizes the carrying amount of our indebtedness (in thousands): December 31, 2017 2016 2021 Notes $ 575,000 $ 575,000 Unamortized discount and debt issuance costs on 2021 Notes (81,627 ) (101,094 ) 2021 Notes, net 493,373 473,906 2024 Notes 575,000 — Unamortized discount and debt issuance costs on 2024 Notes (158,680 ) — 2024 Notes, net 416,320 — Term loan 671,345 705,719 Borrowings under revolving credit facility — 850,000 Total debt 1,581,038 2,029,625 Less current portion 40,605 36,094 Total long-term debt $ 1,540,433 $ 1,993,531 Credit Agreement On June 18, 2015, Jazz Pharmaceuticals plc, as guarantor, and certain of our wholly owned subsidiaries, as borrowers, entered into a credit agreement, which we refer to in this report as the 2015 credit agreement, that provided for a $750.0 million principal amount term loan, which was drawn in full at closing, and a $750.0 million revolving credit facility, of which $160.0 million was drawn at closing and subsequently repaid. We used the proceeds from initial borrowings under the 2015 credit agreement to repay in full the $893.1 million principal amount of term loans outstanding under the credit agreement that we entered into in June 2012, as subsequently amended, which we refer to as the previous credit agreement, and to pay related fees and expenses. The previous credit agreement was terminated upon repayment of the term loans outstanding thereunder. On July 12, 2016 , Jazz Pharmaceuticals plc, as guarantor, and certain of our wholly owned subsidiaries, as borrowers, entered into the amended credit agreement. The amended credit agreement provides for a revolving credit facility of $1.25 billion , which replaced the revolving credit facility of $750.0 million provided for under the 2015 credit agreement, of which no amount was outstanding as of December 31, 2017 , and a $750.0 million term loan facility, of which $676.8 million principal amount was outstanding as of December 31, 2017 . We used the proceeds of $1.0 billion of loans under the revolving credit facility, together with cash on hand, to fund the Celator Acquisition and expect to use the proceeds from future loans under the revolving credit facility, if any, for general corporate purposes, including corporate development activities. Please see Note 3 for additional information regarding the Celator Acquisition. Under the amended credit agreement, the term loan matures on July 12, 2021 and the revolving credit facility terminates, and any loans outstanding thereunder become due and payable, on July 12, 2021 . Borrowings under the amended credit agreement bear interest, at our option, at a rate equal to either (a) the LIBOR rate, plus an applicable margin ranging from 1.50% to 2.25% per annum, based upon our secured leverage ratio, or (b) the prime lending rate, plus an applicable margin ranging from 0.50% to 1.25% per annum, based upon our secured leverage ratio. The revolving credit facility has a commitment fee payable on the undrawn amount ranging from 0.25% to 0.35% per annum based upon our secured leverage ratio. As of December 31, 2017 , the interest rate on the term loan was 3.32% and the effective interest rate was 2.97% . As of December 31, 2017 , we had undrawn revolving credit facilities totaling $1.25 billion . Jazz Pharmaceuticals plc and certain of our wholly owned subsidiaries are borrowers under the amended credit agreement. The borrowers’ obligations under the amended credit agreement and any hedging or cash management obligations entered into with a lender are guaranteed on a senior secured basis by Jazz Pharmaceuticals plc and certain of our subsidiaries (including the issuer of the Exchangeable Senior Notes as described below) and are secured by substantially all of Jazz Pharmaceuticals plc’s, the borrowers’ and the guarantor subsidiaries’ assets. We may make voluntary prepayments of principal at any time without payment of a premium. We are required to make mandatory prepayments of the term loan (without payment of a premium) with (1) net cash proceeds from certain non-ordinary course asset sales (subject to reinvestment rights and other exceptions), (2) net cash proceeds from issuances of debt (other than certain permitted debt), and (3) casualty proceeds and condemnation awards (subject to reinvestment rights and other exceptions). Principal repayments of the term loan, which are due quarterly, began in December 2016 and are equal to 5.0% per annum of the principal amount outstanding on July 12, 2016 of $721.9 million during the first two years, 7.5% per annum during the third year, 10.0% per annum during the fourth year and 12.5% per annum during the fifth year, with any remaining balance payable on the maturity date. The amended credit agreement contains financial covenants that require Jazz Pharmaceuticals plc and our restricted subsidiaries to not (a) exceed a maximum secured net leverage ratio or (b) fall below a cash interest coverage ratio. As of December 31, 2017 , we were in compliance with these financial covenants. In connection with our entry into the amended credit agreement, we recorded a loss on extinguishment and modification of debt of $0.6 million in 2016 primarily related to new third party fees associated with modified debt. In 2015, in connection with our entry into the 2015 credit agreement and termination of the previous credit agreement, we recorded a loss on extinguishment and modification of debt of $16.8 million , which was comprised of $16.0 million related to the expensing of unamortized deferred financing costs and unamortized original issue discount associated with extinguished debt and $0.8 million related to new third party fees associated with modified debt. Exchangeable Senior Notes Due 2024 In the third quarter of 2017, we completed a private placement of $575.0 million principal amount of 2024 Notes. We used the net proceeds from this offering to repay $500.0 million in outstanding loans under the revolving credit facility and to pay related fees and expenses. We used the remainder of the net proceeds for general corporate purposes. Interest on the 2024 Notes is payable semi-annually in cash in arrears on February 15 and August 15 of each year, beginning on February 15, 2018, at a rate of 1.50% per year. In certain circumstances, we may be required to pay additional amounts as a result of any applicable tax withholding or deductions required in respect of payments on the 2024 Notes. The 2024 Notes mature on August 15, 2024, unless earlier exchanged, repurchased or redeemed. The holders of the 2024 Notes have the ability to require us to repurchase all or a portion of their 2024 Notes for cash in the event we undergo certain fundamental changes, such as specified change of control transactions, our liquidation or dissolution or the delisting of our ordinary shares from The NASDAQ Global Select Market. Prior to August 15, 2024, we may redeem the 2024 Notes, in whole but not in part, subject to compliance with certain conditions, if we have, or on the next interest payment date would, become obligated to pay to the holder of any 2024 Notes additional amounts as a result of certain tax-related events. We also may redeem the 2024 Notes on or after August 20, 2021, in whole or in part, if the last reported sale price per ordinary share has been at least 130% of the exchange price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which we provide the notice of redemption. The 2024 Notes are exchangeable at an initial exchange rate of 4.5659 ordinary shares per $1,000 principal amount of 2024 Notes, which is equivalent to an initial exchange price of approximately $219.02 per ordinary share. Upon exchange, the 2024 Notes may be settled in cash, ordinary shares or a combination of cash and ordinary shares, at our election. Our intent and policy is to settle the principal amount of the 2024 Notes in cash upon exchange. The exchange rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain make-whole fundamental changes occurring prior to the maturity date of the 2024 Notes or upon our issuance of a notice of redemption, we will in certain circumstances increase the exchange rate for holders of the 2024 Notes who elect to exchange their 2024 Notes in connection with that make-whole fundamental change or during the related redemption period. Prior to May 15, 2024, the 2024 Notes will be exchangeable only upon satisfaction of certain conditions and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. In accounting for the issuance of the 2024 Notes, we separated the 2024 Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the estimated fair value of a similar liability that does not have an associated exchange feature. The carrying amount of the equity component representing the exchange option was determined by deducting the fair value of the liability component from the face value of the 2024 Notes as a whole. The excess of the principal amount of the liability component over its carrying amount will be amortized to interest expense over the expected life of the 2024 Notes using the effective interest method with an effective interest rate of 6.8% per annum. We have determined the expected life of the 2024 Notes to be equal to the original seven -year term. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. As of December 31, 2017 , the “if-converted value” did not exceed the principal amount of the 2024 Notes. We allocated the total issuance costs incurred of $15.6 million to the liability and equity components based on their relative values. Issuance costs attributable to the liability component will be amortized to expense over the term of the 2024 Notes, and issuance costs attributable to the equity component were included with the equity component in our shareholders’ equity. As of December 31, 2017 , the carrying value of the equity component of the 2024 Notes, net of equity issuance costs, was $149.8 million . Exchangeable Senior Notes Due 2021 In August 2014, we completed a private placement of the 2021 Notes. Interest on the 2021 Notes is payable semi-annually in cash in arrears on February 15 and August 15 of each year , beginning on February 15, 2015, at a rate of 1.875% per year. In certain circumstances, we may be required to pay additional amounts as a result of any applicable tax withholding or deductions required in respect of payments on the 2021 Notes. The 2021 Notes mature on August 15, 2021 , unless earlier exchanged, repurchased or redeemed. The holders of the 2021 Notes have the ability to require us to repurchase all or a portion of their 2021 Notes for cash in the event Jazz Pharmaceuticals plc undergoes certain fundamental changes. Prior to August 15, 2021 , we may redeem the 2021 Notes, in whole but not in part, subject to compliance with certain conditions, if we have, or on the next interest payment date would, become obligated to pay to the holder of any 2021 Note additional amounts as a result of certain tax-related events. We also may redeem the 2021 Notes on or after August 20, 2018 , in whole or in part, if the last reported sale price per ordinary share has been at least 130% of the exchange price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which we provide the notice of redemption. The 2021 Notes are exchangeable at an initial exchange rate of 5.0057 ordinary shares per $1,000 principal amount of 2021 Notes, which is equivalent to an initial exchange price of approximately $199.77 per ordinary share. Upon exchange, the 2021 Notes may be settled in cash, ordinary shares or a combination of cash and ordinary shares, at our election. Our intent and policy is to settle the principal amount of the 2021 Notes in cash upon exchange. The exchange rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain make-whole fundamental changes occurring prior to the maturity date of the 2021 Notes or upon our issuance of a notice of redemption, we will in certain circumstances increase the exchange rate for holders of the 2021 Notes who elect to exchange their 2021 Notes in connection with that make-whole fundamental change or during the related redemption period. Prior to February 15, 2021, the 2021 Notes will be exchangeable only upon satisfaction of certain conditions and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. In accounting for the issuance of the 2021 Notes, we separated the 2021 Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the estimated fair value of a similar liability that does not have an associated exchange feature. The carrying amount of the equity component representing the exchange option was determined by deducting the fair value of the liability component from the face value of the 2021 Notes as a whole. The excess of the principal amount of the liability component over its carrying amount will be amortized to interest expense over the expected life of the 2021 Notes using the effective interest method with an effective interest rate of 6.4% per annum. We have determined the expected life of the 2021 Notes to be equal to the original seven -year term. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. As of December 31, 2017 , the “if-converted value” did not exceed the principal amount of the 2021 Notes. We allocated the total issuance costs incurred of $16.1 million to the liability and equity components based on their relative values. Issuance costs attributable to the liability component will be amortized to expense over the term of the 2021 Notes, and issuance costs attributable to the equity component were included with the equity component in our shareholders’ equity. As of December 31, 2017 , the carrying value of the equity component of the 2021 Notes, net of equity issuance costs, was $126.9 million . The Exchangeable Senior Notes were issued by Jazz Investments I Limited, or the Issuer, a 100% -owned finance subsidiary of Jazz Pharmaceuticals plc. The Exchangeable Senior Notes are senior unsecured obligations of the Issuer and are fully and unconditionally guaranteed on a senior unsecured basis by Jazz Pharmaceuticals plc. No subsidiary of Jazz Pharmaceuticals plc guaranteed the Exchangeable Senior Notes. Subject to certain local law restrictions on payment of dividends, among other things, and potential negative tax consequences, we are not aware of any significant restrictions on the ability of Jazz Pharmaceuticals plc to obtain funds from the Issuer or Jazz Pharmaceuticals plc’s other subsidiaries by dividend or loan, or any legal or economic restrictions on the ability of the Issuer or Jazz Pharmaceuticals plc’s other subsidiaries to transfer funds to Jazz Pharmaceuticals plc in the form of cash dividends, loans or advances. There is no assurance that in the future such restrictions will not be adopted. For the years ended December 31, 2017 , 2016 and 2015 , we recognized $37.8 million , $27.5 million and $26.5 million , respectively, in interest expense, net related to the contractual coupon rate and amortization of the debt discount on the Exchangeable Senior Notes. Scheduled maturities with respect to our long-term debt are as follows (in thousands): Year Ending December 31, Scheduled Long-Term Debt Maturities 2018 $ 40,605 2019 58,652 2020 76,700 2021 1,075,801 Thereafter 575,000 Total $ 1,826,758

Deferred Revenue

Deferred Revenue	12 Months Ended
	Dec. 31, 2017
Other Liabilities [Abstract]
Deferred Revenue	Deferred Revenue The deferred revenue balance as of December 31, 2017 primarily related to deferred upfront fees received in connection with two license, development and commercialization agreements. We recognized contract revenues of $5.6 million during 2017 relating to these upfront payments. The deferred revenue balances are being recognized over an average of four years representing the period we expect to perform our research and developments obligations under each agreement. The deferred revenue balance as of December 31, 2016 primarily related to agreements we have with UCB Pharma Limited, or UCB, under which UCB has the right to market Xyrem for certain indications in various countries outside of the U.S. We recognized contract revenues of $1.1 million during each of 2017 , 2016 and 2015 relating to two upfront payments received from UCB in 2006 totaling $15.0 million .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Indemnification In the normal course of business, we enter into agreements that contain a variety of representations and warranties and provide for general indemnification, including indemnification associated with product liability or infringement of intellectual property rights. Our exposure under these agreements is unknown because it involves future claims that may be made but have not yet been made against us. To date, we have not paid any claims or been required to defend any action related to these indemnification obligations. We have agreed to indemnify our executive officers, directors and certain other employees for losses and costs incurred in connection with certain events or occurrences, including advancing money to cover certain costs, subject to certain limitations. The maximum potential amount of future payments we could be required to make under the indemnification obligations is unlimited; however, we maintain insurance policies that may limit our exposure and may enable us to recover a portion of any future amounts paid. Assuming the applicability of coverage, the willingness of the insurer to assume coverage, and subject to certain retention, loss limits and other policy provisions, we believe the fair value of these indemnification obligations is not significant. Accordingly, we have not recognized any liabilities relating to these obligations as of December 31, 2017 and December 31, 2016 . No assurances can be given that the covering insurers will not attempt to dispute the validity, applicability, or amount of coverage without expensive litigation against these insurers, in which case we may incur substantial liabilities as a result of these indemnification obligations. Lease and Other Commitments Facility Leases. In January 2015, we entered into an agreement to lease office space located in Palo Alto, California in a building subsequently constructed by the landlord. The term of this lease is 12 years from the commencement date as defined in the lease agreement and we have an option to extend the term twice for a period of five years each. We concluded we were the deemed owner of the building during the construction period, based on applicable accounting guidance for build-to-suit leases. Accordingly, the landlord’s costs of constructing the building during the construction period were capitalized, offset by a corresponding financing obligation in our consolidated balance sheets. We began to occupy this office space in October 2017. As such, we evaluated the lease to determine whether it had met the requirements for sale-leaseback accounting, including evaluating whether all risks of ownership have been transferred back to the landlord, as evidenced by a lack of continuing involvement in the build-to-suit lease property. We determined that the construction project did not qualify for sale-leaseback accounting and will instead be accounted for as a financing, given our continuing involvement after the conclusion of the construction period. As a result, the build-to-suit lease property remains on our consolidated balance sheets as of December 31, 2017 and is being depreciated over its estimated useful life starting in the fourth quarter of 2017. As of December 31, 2017 , the total amount of the related financing obligation was $62.9 million , which is classified within current liabilities and non-current liabilities in our consolidated balance sheets. In September 2017, we entered into an agreement to lease office space located in Palo Alto, California in a second building to be constructed by the same landlord. We expect to occupy this office space by the end of 2019. This lease has a term of 12 years from the commencement date as defined in the lease agreement and we have an option to extend the term of the lease twice for a period of five years each. In connection with this lease, the landlord is providing a tenant improvement allowance for the costs associated with the design, development and construction of tenant improvements for the leased facilities. We are obligated to fund all costs incurred in excess of the tenant improvement allowance. The scope of the planned tenant improvements do not qualify as “normal tenant improvements” under the lease accounting guidance. Accordingly, for accounting purposes, we have concluded we are the deemed owner of the building during the construction period. As of December 31, 2017 , we recorded project construction costs of $17.4 million incurred by the landlord as construction-in-progress in property and equipment, net and a corresponding financing obligation in other non-current liabilities in our consolidated balance sheets. We will increase the asset and financing obligation as additional building costs are incurred by the landlord during the construction period. For the years ended December 31, 2017, 2016 and 2015, we recorded rent expense associated with the ground lease on our facility leases of $2.4 million , $1.9 million and $1.8 million , respectively, in our consolidated statements of income. Future minimum lease payments under our noncancelable facility leases as of December 31, 2017 , were as follows (in thousands): Year Ending December 31, Lease Payments 2018 $ 6,297 2019 9,142 2020 14,392 2021 14,824 2022 15,269 Thereafter 135,473 Total $ 195,397 Operating Leases. We have noncancelable operating leases for our office buildings and we are obligated to make payments under noncancelable operating leases for automobiles used by our sales force. Lease expense under our operating leases was as follows (in thousands): Year Ended December 31, 2017 2016 2015 Lease expense $ 14,982 $ 11,600 $ 10,479 Future minimum lease payments under our noncancelable operating leases as of December 31, 2017 , were as follows (in thousands): Year ending December 31, Lease Payments 2018 $ 9,102 2019 8,166 2020 6,111 2021 5,212 2022 5,007 Thereafter 12,753 Total $ 46,351 In August 2016, we entered into an operating lease agreement for office space in Dublin, Ireland for a term of 20 years , with an option to terminate at the end of eight years with no less than one year ’s prior written notice and the payment of a termination fee, and a further option to terminate at the end of 15 years with no less than one year ’s prior written notice. We are obligated to make minimum lease payments totaling $19.8 million in connection with this lease. Other Commitments. As of December 31, 2017 , we had $46.3 million of noncancelable purchase commitments due within one year, primarily related to agreements with third party manufacturers. Legal Proceedings We are involved in legal proceedings, including the following matters: Xyrem ANDA Litigation. On December 10, 2012, we received a notice of Paragraph IV Patent Certification, or Paragraph IV Certification, from Amneal Pharmaceuticals, LLC, or Amneal, that it had submitted an abbreviated new drug application, or ANDA, to the FDA requesting approval to market a generic version of Xyrem. On January 18, 2013, we filed a lawsuit against Amneal in the federal district court of New Jersey, or District Court, alleging that our patents covering Xyrem are infringed or will be infringed by Amneal’s ANDA and seeking a permanent injunction to prevent Amneal from introducing a generic version of Xyrem that would infringe these patents. On November 21, 2013, we received a notice of Paragraph IV Certification from Par Pharmaceutical, Inc., or Par, that it had submitted an ANDA to the FDA requesting approval to market a generic version of Xyrem. On December 27, 2013, we filed a lawsuit against Par in the District Court alleging that our patents covering Xyrem are infringed or will be infringed by Par’s ANDA and seeking a permanent injunction to prevent Par from introducing a generic version of Xyrem that would infringe these patents. In May 2014, the District Court granted a request by Amneal to consolidate its case with the Par case. Additional patents covering Xyrem have been issued since May 2014 and have been listed in the FDA’s publication “Approved Drug Products with Therapeutic Equivalence Evaluations,” or the Orange Book, for Xyrem. Amneal and Par gave us additional notices of Paragraph IV Certifications regarding such patents, and we filed additional lawsuits against Amneal and Par in the District Court alleging that our patents covering Xyrem are infringed or will be infringed by Amneal’s and Par’s ANDAs and seeking a permanent injunction to prevent Amneal and Par from introducing a generic version of Xyrem that would infringe our patents. In August 2016, we and Par stipulated to dismiss claims relating to our patents covering the formulation of Xyrem on the grounds that Par had notified FDA that it had converted its Paragraph IV Certifications to Paragraph III Patent Certifications. In September 2017, we and Amneal stipulated to dismiss claims relating to certain of our patents covering the formulation of Xyrem on the grounds that Amneal had notified FDA that it had converted its Paragraph IV Certifications as to these patents to Paragraph III Patent Certifications. On October 30, 2014, we received a notice of Paragraph IV Certification from Teva Pharmaceutical Industries Ltd., formerly known as Watson Laboratories, Inc., or Teva, that it had submitted an ANDA to the FDA requesting approval to market a generic version of Xyrem. On December 11, 2014, we filed a lawsuit against Teva in the District Court alleging that our patents covering Xyrem are or will be infringed by Teva’s ANDA and seeking a permanent injunction to prevent Teva from introducing a generic version of Xyrem that would infringe these patents. In March 2015, Teva moved to dismiss the portion of the case based on our Orange Book-listed REMS patents on the grounds that these patents do not cover patentable subject matter. In November 2015, the District Court administratively terminated this motion to dismiss (without prejudice) pending the outcome of IPR proceedings before the Patent Trial and Appeal Board, or PTAB, of the U.S. Patent and Trademark Office relating to the patents that were the subject of Teva’s motion. Since March 2015, we received an additional notice of Paragraph IV Certification from Teva regarding newly issued patents for Xyrem listed in the Orange Book, and we filed an additional lawsuit against Teva in the District Court alleging that our patents covering Xyrem are or will be infringed by Teva’s ANDA and seeking a permanent injunction to prevent Teva from introducing a generic version of Xyrem that would infringe these patents. In April 2015, the District Court issued an order consolidating all then-pending lawsuits against Amneal, Par and Teva into one case. On July 23, 2015, we received a notice of Paragraph IV Certification from Lupin Inc., or Lupin, that it had submitted an ANDA to the FDA requesting approval to market a generic version of Xyrem. On September 2, 2015, we filed a lawsuit in the District Court alleging that our patents covering Xyrem are or will be infringed by Lupin’s ANDA and seeking a permanent injunction to prevent Lupin from introducing a generic version of Xyrem that would infringe our patents. In January, April and June 2016, the District Court issued orders consolidating all of the cases then pending against Amneal, Par, Teva and Lupin into a single case for all purposes. Although no trial date has been set for the consolidated case, discovery is scheduled to conclude in the third quarter of 2018, and the trial in this consolidated case could occur as early as the third quarter of 2018. As discussed in more detail below, in January 2018, we entered into a settlement agreement and related agreements resolving our patent infringement litigation against Par in the consolidated case, as well as related discovery proceedings and certain IPR proceedings currently on appeal to the Court of Appeal for the Federal Circuit, or the Federal Circuit. On November 21, 2017, we received a notice of Paragraph IV Certification from Mallinckrodt Inc., or Mallinckrodt, that it had submitted an ANDA to the FDA requesting approval to market a generic version of Xyrem. On January 2, 2018, we filed a lawsuit in the District Court alleging that our patents covering Xyrem are or will be infringed by Mallinckrodt’s ANDA and seeking a permanent injunction to prevent Mallinckrodt from introducing a generic version of Xyrem that would infringe our patents. We cannot predict whether additional generic manufacturers will file ANDAs and require new patent litigation, the specific timing or outcome of events with respect to the remaining defendants or the impact of developments involving any specific parties or patents on other ongoing proceedings with any ANDA filer. Xyrem ANDA Litigation Settlements. On April 5, 2017, we entered into a settlement agreement and related agreements resolving our patent infringement litigation against the first ANDA filer, Roxane Laboratories, Inc., which was acquired by West-Ward Pharmaceuticals Corp. (a wholly owned subsidiary of Hikma Pharmaceuticals PLC), or West-Ward. In connection with the settlement, we granted West-Ward the right to sell an authorized generic version of Xyrem, the West-Ward AG Product, in the U.S. for an initial term of six months beginning on January 1, 2023, or earlier under certain circumstances. Such circumstances include events related to the licensing or market entry of another generic sodium oxybate product, a final decision that all unexpired claims of the Xyrem patents are invalid and/or unenforceable, or a substantial reduction in Xyrem net sales over specified periods of time. West-Ward has the right to extend the initial six -month term for the West-Ward AG Product, or the Initial Term, and continue to sell the West-Ward AG Product for up to a total of five years (the Initial Term, as it may be extended by West-Ward, is referred to as the West-Ward AG Sales Period). We are entitled to receive a meaningful royalty on net sales of the West-Ward AG Product, with the royalty rate increasing during the Initial Term based on increased net sales of the West-Ward AG Product. There will also be a substantial increase in the royalty rate should the West-Ward AG Sales Period be extended beyond one year . We will also receive payment for the supply of the West-Ward AG Product and reimbursement for a portion of the services costs associated with the operation of the Xyrem REMS and distribution of the West-Ward AG Product. We also granted West-Ward a non-exclusive license under the Xyrem patents to make, have made and market its own generic sodium oxybate product under the West-Ward ANDA in the U.S., effective at the end of the West-Ward AG Sales Period. On January 9, 2018, we entered into a settlement agreement and related agreements resolving our patent infringement litigation against Par in the District Court, as well as related discovery proceedings and certain IPR proceedings currently on appeal to the Federal Circuit. In connection with the settlement, we granted Par the right to sell a limited volume of an authorized generic version of Xyrem, or the Par AG Product, in the U.S. for a term beginning on July 1, 2023, or earlier under certain circumstances, and ending on December 31, 2025, or the Par AG Sales Period. Such circumstances include events related to acceleration of the West-Ward AG Product launch date, the earlier launch of another party’s authorized generic or generic sodium oxybate product, or a final decision that all unexpired claims of the Xyrem patents are not infringed, invalid and/or unenforceable. The volume of the Par AG Product is limited to an annual amount equal to a low single-digit percentage of Xyrem sales volume during the calendar year preceding the entry date of the Par AG Product. We also granted Par a non-exclusive license under the Xyrem patents to make, have made and market its own generic sodium oxybate product under Par’s ANDA (assuming FDA approval is obtained) effective December 31, 2025, or earlier under certain circumstances. Such circumstances include events related to launch of a generic sodium oxybate product by West-Ward or another party under its ANDA, or a final decision that all unexpired claims of the Xyrem patents are not infringed, invalid and/or unenforceable. If the Par license to market its own generic sodium oxybate product accelerates, then Par will have the option to elect to market the Par AG Product until December 31, 2025, but Par will not be entitled to market the Par AG Product and its own generic sodium oxybate product simultaneously. We are entitled to receive a meaningful royalty on net sales of the Par AG Product over the Par AG Sales Period, as well as payment for the supply of the Par AG Product and reimbursement for a portion of the services costs associated with the operation of the Xyrem REMS and distribution of the Par AG Product. In addition to our settlement agreements with West-Ward and Par, we have also entered into settlements with three other ANDA filers, granting each of those filers the right to manufacture, market and sell its own sodium oxybate product on or after December 31, 2025, or earlier depending on the occurrence of certain events. The specific terms of all of the settlement agreements are confidential. The settlements do not resolve the consolidated case against Amneal, Teva and Lupin, or the case against the most recent ANDA filer, Mallinckrodt, which remain pending. Xyrem Post-Grant Patent Review Matters . In January 2015, certain of the ANDA filers filed petitions for IPR with respect to the validity of six of our seven patents associated with the Xyrem REMS, or REMS patents. The PTAB instituted IPR trials with respect to certain of these petitions. In July 2016, the PTAB issued final decisions that the claims of the six REMS patents are unpatentable. In March 2016, the PTAB partially instituted an IPR on three claims of a seventh REMS patent, declining to review 25 of 28 claims, and in March 2017, the PTAB issued a final decision that the three claims they reviewed are unpatentable. The July 2016 and March 2017 PTAB decisions are part of a consolidated appeal currently pending before the Federal Circuit. If the Federal Circuit upholds the PTAB decisions on appeal, we will not be able to enforce claims the PTAB found unpatentable. We cannot predict whether additional post-grant patent review challenges will be filed by any of the ANDA filers or any other entity, the outcome of any future IPR or other proceeding, the outcome of the appeal of the July 2016 and March 2017 PTAB decisions with respect to the REMS patents or the impact any IPR or other proceeding might have on ongoing ANDA litigation proceedings or other aspects of our Xyrem business. Shareholder Litigation Matters Relating to Celator Acquisition. On June 21, 2016, a putative class-action lawsuit challenging our Celator Acquisition, captioned Dunbar v. Celator Pharmaceuticals, Inc., or the Dunbar action, was filed in the Superior Court of New Jersey. The complaint was filed against Celator, each member of the Celator board of directors, Jazz Pharmaceuticals plc and our wholly owned subsidiary Plex Merger Sub, Inc., or Plex. The complaint generally alleges that the Celator directors breached their fiduciary duties in connection with the Celator Acquisition, and that Jazz Pharmaceuticals plc and Plex aided and abetted these alleged breaches of fiduciary duty. The complaint also generally asserts that the Celator directors breached their fiduciary duties to Celator’s public stockholders by, among other things, (i) agreeing to sell Celator to us at an inadequate price, (ii) implementing an unfair process, (iii) agreeing to certain provisions of the merger agreement for the Celator Acquisition that allegedly favored us and deterred alternative bids, and (iv) failing to disclose purportedly material information in Celator’s Schedule 14D-9 filing with the U.S. Securities and Exchange Commission, or SEC. The plaintiff sought, among other things, an injunction against the consummation of the Celator Acquisition and an award of costs and expenses, including a reasonable allowance for attorneys’ and experts’ fees. Between June 27, 2016 and June 29, 2016, two putative class-action lawsuits challenging the Celator Acquisition, captioned Palmisciano v. Celator Pharmaceuticals, Inc., or the Palmisciano action, and Barreto v. Celator Pharmaceuticals, Inc. , or the Barreto action , were filed in the District Court. The complaints were filed against Celator and each member of the Celator board of directors. The complaints assert causes of action under sections 14 and 20 of the Securities Exchange Act of 1934, as amended, predicated on Celator’s and the Celator directors’ alleged failure to disclose purportedly material information in Celator’s Schedule 14D-9 filing with the SEC. The plaintiffs sought, among other things, an injunction against the consummation of the Celator Acquisition and an award of costs and expenses, including a reasonable allowance for attorneys’ and experts’ fees. Neither Jazz Pharmaceuticals plc nor Plex were named defendants in these actions. On July 6, 2016, the defendants to the Dunbar action, the Palmisciano action and the Barreto action entered into a memorandum of understanding, or MOU, regarding settlement of these actions with the plaintiffs. The MOU outlines the terms of the parties’ agreement in principle to settle and release all claims which were or could have been asserted in these actions. In consideration for such settlement and release, the parties to these actions agreed, among other things, that Celator would amend its Schedule 14D-9 to include certain supplemental disclosures. The Schedule 14D-9 was amended by Celator on July 6, 2016, and the Celator Acquisition was completed on July 12, 2016. In June 2017, the parties to the MOU agreed to terminate the MOU, and the plaintiffs agreed to voluntarily dismiss the remaining actions. Thereafter, the parties negotiated and ultimately agreed, in October 2017, on a mootness fee paid to plaintiffs’ counsel. The Dunbar, Palmisciano and Barreto actions have each been dismissed with prejudice. From time to time we are involved in legal proceedings arising in the ordinary course of business. We believe there is no other litigation pending that could have, individually or in the aggregate, a material adverse effect on our results of operations or financial condition. Other Contingencies In May and October 2016 and in February 2017, we received subpoenas from the U.S. Attorney’s Office for the District of Massachusetts requesting documents related to our support of 501(c)(3) organizations that provide financial assistance to Medicare patients, and, for Xyrem, documents concerning the provision of financial assistance to Medicare patients. Other companies have disclosed similar subpoenas and continuing inquiries. We are cooperating with the government’s investigation of our support of charitable organizations, and the outcome of this investigation could include an enforcement action or a settlement with the federal government. We are unable to predict how long this investigation will continue, whether we will receive additional subpoenas in connection with this investigation, or its outcome, but we expect that we will continue to incur significant costs in connection with the investigation, regardless of the outcome. If the federal government were to file an enforcement action against us as a result of the investigation and could establish the elements of a violation of relevant laws, we could be subject to damages, fines and penalties, which could be substantial, along with other criminal, civil or administrative sanctions. Any settlement with the federal government could result in substantial payments and entry into a corporate integrity agreement, which would impose costs and burdens on the operation of our business.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity Share Repurchase Program In May 2013, our board of directors authorized a share repurchase program pursuant to which we were authorized to repurchase a number of ordinary shares having an aggregate repurchase price of up to $200.0 million , exclusive of any brokerage commissions. In August 2015, we completed repurchases under the May 2013 share repurchase program. In November 2015, our board of directors authorized another share repurchase program pursuant to which we were authorized to repurchase a number of ordinary shares having an aggregate purchase price of up to $300.0 million , exclusive of any brokerage commissions. In September 2016, we completed repurchases under the November 2015 share repurchase program. In November 2016, our board of directors authorized a new share repurchase program pursuant to which we are authorized to repurchase a number of ordinary shares having an aggregate purchase price of up to $300.0 million , exclusive of any brokerage commissions. Under this program, which has no expiration date, we may repurchase ordinary shares from time to time on the open market. The timing and amount of repurchases will depend on a variety of factors, including the price of our ordinary shares, alternative investment opportunities, restrictions under the amended credit agreement, corporate and regulatory requirements and market conditions. The new share repurchase program may be modified, suspended or discontinued at any time without prior notice. In 2017 , under the November 2016 repurchase program, we spent a total of $98.8 million to repurchase 0.7 million of our ordinary shares at an average total purchase price, including brokerage commissions, of $140.34 per share. All ordinary shares repurchased were canceled. As of December 31, 2017 , the remaining amount authorized under the November 2016 share repurchase program was $182.7 million . Authorized But Unissued Ordinary Shares We had reserved the following shares of authorized but unissued ordinary shares (in thousands): December 31, 2017 2011 Equity Incentive Plan 16,026 Amended and Restated 2007 Non-Employee Directors Stock Award Plan 481 2007 Employee Stock Purchase Plan 339 Amended and Restated Directors Deferred Compensation Plan 178 2007 Equity Incentive Plan 17 Total 17,041

Comprehensive Income (Loss)

Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) includes net income and all changes in shareholders’ equity during a period, except for those changes resulting from investments by shareholders or distributions to shareholders. Accumulated Other Comprehensive Loss The components of accumulated other comprehensive loss as of December 31, 2017 and December 31, 2016 were as follows (in thousands): Net Unrealized Foreign Total Balance at December 31, 2016 $ — $ (317,333 ) $ (317,333 ) Other comprehensive income (loss) before reclassifications (213 ) 174,973 174,760 Amounts reclassified from accumulated other comprehensive loss 1,695 — 1,695 Other comprehensive income, net 1,482 174,973 176,455 Balance at December 31, 2017 $ 1,482 $ (142,360 ) $ (140,878 ) In 2017 , other comprehensive income reflects foreign currency translation adjustments, primarily due to the strengthening of the euro against the U.S. dollar, and the net unrealized gain on derivatives that qualify as cash flow hedges.

Segment and Other Information

Segment and Other Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segment and Other Information	Segment and Other Information Our operating segment is reported in a manner consistent with the internal reporting provided to the chief operating decision maker or, CODM. Our CODM has been identified as our chief executive officer. We have determined that we operate in one business segment, which is the identification, development and commercialization of meaningful pharmaceutical products that address unmet medical needs. The following table presents a summary of total revenues (in thousands): Year Ended December 31, 2017 2016 2015 Xyrem $ 1,186,699 $ 1,107,616 $ 955,187 Erwinaze/Erwinase 197,340 200,678 203,261 Defitelio/defibrotide 133,650 108,952 70,731 Vyxeos 33,790 — — Prialt ® (ziconotide) intrathecal infusion 27,361 29,120 26,440 Other 22,559 30,895 61,200 Product sales, net 1,601,399 1,477,261 1,316,819 Royalties and contract revenues 17,294 10,712 7,984 Total revenues $ 1,618,693 $ 1,487,973 $ 1,324,803 The following table presents a summary of total revenues attributed to geographic sources (in thousands): Year Ended December 31, 2017 2016 2015 United States $ 1,463,457 $ 1,354,921 $ 1,192,879 Europe 122,789 106,146 103,614 All other 32,447 26,906 28,310 Total revenues $ 1,618,693 $ 1,487,973 $ 1,324,803 The following table presents a summary of the percentage of total revenues from customers that represented more than 10% of our total revenues: Year Ended December 31, 2017 2016 2015 Express Scripts 73 % 74 % 72 % McKesson 16 % 15 % 7 % At the end of the second quarter of 2015, we transitioned the U.S. distribution of Erwinaze from Accredo Health Group, Inc. to McKesson. The following table presents total long-lived assets by location (in thousands): December 31, 2017 2016 United States $ 95,570 $ 35,791 Ireland 64,343 62,453 Italy 8,220 7,000 Other 1,947 2,246 Total long-lived assets (1) $ 170,080 $ 107,490 _________________________ (1) Long-lived assets consist of property and equipment.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation 2011 Equity Incentive Plan On January 18, 2012, the businesses of Jazz Pharmaceuticals, Inc. and Azur Pharma were combined in a merger transaction, or the Azur Merger. In connection with the Azur Merger, Jazz Pharmaceuticals, Inc.’s board of directors adopted the 2011 Equity Incentive Plan, or the 2011 Plan, in October 2011 and its stockholders approved the 2011 Plan at the special meeting of the stockholders held in December 2011 in connection with the Azur Merger. The 2011 Plan became effective immediately before the consummation of the Azur Merger and was assumed and adopted by us upon the consummation of the Azur Merger. The terms of the 2011 Plan provide for the grant of stock options, stock appreciation rights, restricted stock awards, RSUs, other stock awards, and performance awards that may be settled in cash, shares, or other property. All outstanding grants under the 2011 Plan were granted to employees and vest ratably over service periods of four years and expire no more than 10 years after the date of grant. As of December 31, 2017 , a total of 21,729,232 of our ordinary shares had been authorized for issuance under the 2011 Plan. In addition, the share reserve under the 2011 Plan will automatically increase on January 1 of each year through January 1, 2022, by the least of (a) 4.5% of the total number of ordinary shares outstanding on December 31 of the preceding calendar year, (b) 5,000,000 shares, or (c) such lesser number of ordinary shares as determined by our board of directors. On January 1, 2018, the share reserve under the 2011 Plan automatically increased by 2,695,413 ordinary shares pursuant to this provision. 2007 Equity Incentive Plan The 2007 Equity Incentive Plan, or the 2007 Plan, which was initially adopted by the Jazz Pharmaceuticals, Inc. board of directors and approved by the Jazz Pharmaceuticals, Inc. stockholders in connection with its initial public offering, was continued and assumed by us upon consummation of the Azur Merger. The 2007 Plan provided for the grant of stock options, restricted stock awards, RSUs, stock appreciation rights, performance stock awards and other forms of equity compensation to employees, including officers, non-employee directors and consultants. Prior to the consummation of the Azur Merger, all of the grants under the 2007 Plan were granted to employees and vest ratably over service periods of three to five years and expire no more than 10 years after the date of grant. Effective as of the closing of the Azur Merger on January 18, 2012, the number of shares reserved for issuance under the 2007 Plan was set to 1,000,000 ordinary shares. The share reserve under the 2007 Plan will not automatically increase. Since the Azur Merger, all of the new grants under the 2007 Plan were granted to non-employee directors, vest ratably over service periods of one to three years and expire no more than 10 years after the date of grant. The 2007 Plan expired in April 2017, and accordingly, no new grants can be awarded under the 2007 Plan. As of December 31, 2017 , the number of shares reserved represents issuable shares from options granted but not yet exercised under the 2007 Plan. 2007 Employee Stock Purchase Plan In 2007, Jazz Pharmaceuticals, Inc.’s employees became eligible to participate in the ESPP. The ESPP was amended and restated by Jazz Pharmaceuticals, Inc.’s board of directors in October 2011 and approved by its stockholders in December 2011. The amended and restated ESPP became effective immediately prior to the effective time of the Azur Merger and was assumed by us upon the consummation of the Azur Merger. The amended and restated ESPP allows our eligible employee participants (including employees of any of a parent or subsidiary company if our board of directors designates such company as eligible to participate) to purchase our ordinary shares at a discount of 15% through payroll deductions. The ESPP consists of a fixed offering period of 24 months with four purchase periods within each offering period. The number of shares available for issuance under our ESPP during any six-month purchase period is 175,000 shares. As of December 31, 2017 , a total of 2,660,000 of our ordinary shares had been authorized for issuance under the ESPP. The share reserve under the ESPP will automatically increase on January 1 of each year through January 1, 2022, by the least of (a) 1.5% of the total number of ordinary shares outstanding on December 31 of the preceding calendar year, (b) 1,000,000 shares, and (c) such lesser number of ordinary shares as determined by our board of directors or a duly-authorized committee thereof. On January 1, 2018, the share reserve under the ESPP automatically increased by 898,471 ordinary shares pursuant to this provision. Amended and Restated 2007 Non-Employee Directors Stock Award Plan The Amended and Restated 2007 Non-Employee Directors Stock Award Plan, or the 2007 Directors Award Plan, which was initially adopted by the Jazz Pharmaceuticals, Inc. board of directors and approved by the Jazz Pharmaceuticals, Inc. stockholders in connection with its initial public offering, was continued and assumed by us upon the consummation of the Azur Merger. Until October 2011, the 2007 Directors Award Plan provided for the automatic grant of stock options to purchase shares of Jazz Pharmaceuticals, Inc.’s common stock to its non-employee directors initially at the time any individual first became a non-employee director, which vest over three years, and then annually over their period of service on its board of directors, which vest over one year. On October 24, 2011, Jazz Pharmaceuticals, Inc.’s board of directors amended the 2007 Directors Award Plan to eliminate all future initial and annual automatic grants so that future automatic grants would not be made that would be subject to the excise tax imposed by Section 4985 of the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code, in connection with the Azur Merger. Accordingly, all future stock option grants under the 2007 Directors Award Plan will be at the discretion of our board of directors. Since the Azur Merger, all of the new grants under the 2007 Directors Award Plan were granted to non-employee directors and vest ratably over service periods of one to three years and expire no more than 10 years after the date of grant. In addition, the 2007 Directors Award Plan provides the source of shares to fund distributions made prior to August 15, 2010 under the Directors Deferred Compensation Plan described below. In August 2016, our shareholders approved our proposal to expand the types of stock awards that may be granted to our non-employee directors under the 2007 Directors Award Plan and eliminate the final automatic share reserve increase under the 2007 Directors Award Plan that was scheduled to occur on January 1, 2017. As of December 31, 2017 , a total of 903,938 of our ordinary shares had been authorized for issuance under the 2007 Directors Award Plan. Amended and Restated Directors Deferred Compensation Plan In May 2007, the Jazz Pharmaceuticals, Inc. board of directors adopted the Directors Deferred Compensation Plan, or the Directors Deferred Plan, which was amended in December 2008 and was then amended and restated in August 2010, and which was continued and assumed by us upon consummation of the Azur Merger. The Directors Deferred Plan allows each non-employee director to elect to defer receipt of all or a portion of his or her annual retainer fees to a future date or dates. Amounts deferred under the Directors Deferred Plan are credited as shares of Jazz Pharmaceuticals, Inc.’s common stock (or our ordinary shares following the Azur Merger) to a phantom stock account, the number of which are based on the amount of the retainer fees deferred divided by the market value of Jazz Pharmaceuticals, Inc.’s common stock (or our ordinary shares following the Azur Merger) on the first trading day of the first open window period following the date the retainer fees are deemed earned. On the 10th business day following the day of separation from the board of directors or the occurrence of a change in control, or as soon thereafter as practical once the non-employee director has provided the necessary information for electronic deposit of the deferred shares, each non-employee director will receive (or commence receiving, depending upon whether the director has elected to receive distributions from his or her phantom stock account in a lump sum or in installments over time) a distribution of his or her phantom stock account, in our ordinary shares (i) reserved under the 2007 Directors Option Plan prior to August 15, 2010 and (ii) from a new reserve of 200,000 shares set up under the Directors Deferred Plan on August 15, 2010. Although we continue to maintain the Directors Deferred Plan, since the consummation of the Azur Merger we have not permitted and will not permit non-employee directors to defer any annual retainer fees under the Directors Deferred Plan. We recorded no expense in 2017, 2016 and 2015 related to retainer fees earned and deferred. As of December 31, 2017 , 14,499 of our ordinary shares that were unissued related to retainer fees that were deferred under the Directors Deferred Plan. Share-Based Compensation The table below shows, for all share option grants, the weighted-average assumptions used in the Black-Scholes option pricing model and the resulting weighted-average grant date fair value of share options granted in each of the past three years: Year Ended December 31, 2017 2016 2015 Grant date fair value $ 42.72 $ 40.45 $ 57.19 Volatility 35 % 39 % 39 % Expected term (years) 4.3 4.2 4.2 Range of risk-free rates 1.6-2.1% 0.8-1.6% 1.1-1.5% Expected dividend yield — % — % — % We rely on a blend of the historical and implied volatilities of our own ordinary shares to determine expected volatility for share option grants. In addition, we use a single volatility estimate for each share option grant. The weighted-average volatility is determined by calculating the weighted average of volatilities for all share options granted in a given year. The expected term of share option grants represents the weighted-average period the awards are expected to remain outstanding and our estimates were based on historical exercise data. The risk-free interest rate assumption was based on zero coupon U.S. Treasury instruments whose term was consistent with the expected term of our share option grants. The expected dividend yield assumption was based on our history and expectation of dividend payouts. Share-based compensation expense related to share options, RSUs and grants under our ESPP was as follows (in thousands): Year Ended December 31, 2017 2016 2015 Selling, general and administrative $ 83,218 $ 79,037 $ 74,653 Research and development 17,870 15,296 13,356 Cost of product sales 5,812 4,438 3,541 Total share-based compensation expense, pre-tax 106,900 98,771 91,550 Income tax benefit from share-based compensation expense (1) (21,792 ) (30,022 ) (20,071 ) Total share-based compensation expense, net of tax $ 85,108 $ 68,749 $ 71,479 __________________________ (1) Following adoption of ASU No. 2016-09 “Improvements to Employee Share-Based Payment Accounting” in 2016, the 2017 and 2016 income tax benefit includes excess tax benefits recognized. We recognized income tax benefits related to share option exercises of $8.9 million and $8.3 million in 2017 and 2016 , respectively, and realized $0.4 million in 2015 . Share Options The following table summarizes information as of December 31, 2017 and activity during 2017 related to our share option plans: Shares Subject to Outstanding Options (In thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (In thousands) Outstanding at January 1, 2017 4,513 $ 111.52 Options granted 1,402 137.46 Options exercised (428 ) 53.03 Options forfeited (241 ) 140.04 Options expired (101 ) 165.49 Outstanding at December 31, 2017 5,145 121.06 6.8 $ 124,032 Vested and expected to vest at December 31, 2017 4,896 120.27 6.7 123,206 Exercisable at December 31, 2017 2,976 108.45 5.6 116,822 Aggregate intrinsic value shown in the table above is equal to the difference between the exercise price of the underlying share options and the fair value of our ordinary shares for share options that were in the money. The aggregate intrinsic value changes based on the fair market value of our ordinary shares. The aggregate intrinsic value of share options exercised was $38.9 million , $36.1 million and $93.3 million during 2017 , 2016 and 2015 , respectively. We issued new ordinary shares upon exercise of share options. As of December 31, 2017 , total compensation cost not yet recognized related to unvested share options was $73.4 million , which is expected to be recognized over a weighted-average period of 2.6 years. As of December 31, 2017 , total compensation cost not yet recognized related to grants under the ESPP was $2.8 million , which is expected to be recognized over a weighted-average period of less than one year . Restricted Stock Units In 2017 , we granted RSUs covering an equal number of our ordinary shares to employees with a weighted-average grant date fair value of $137.46 . The fair value of RSUs is determined on the date of grant based on the market price of our ordinary shares as of that date. The fair value of the RSUs is recognized as an expense ratably over the vesting period of four years . In 2017 , 385,000 RSUs were released with 250,000 ordinary shares issued and 135,000 ordinary shares withheld for tax purposes. The total fair value of shares vested was $53.2 million , $59.2 million and $72.2 million during 2017 , 2016 and 2015 , respectively. As of December 31, 2017 , total compensation cost not yet recognized related to unvested RSUs was $88.6 million , which is expected to be recognized over a weighted-average period of 2.4 years. The following table summarizes information as of December 31, 2017 and activity during 2017 related to our RSUs: Number of RSUs (in thousands) Weighted- Weighted- Aggregate Outstanding at January 1, 2017 997 $ 137.50 RSUs granted 561 137.46 RSUs released (385 ) 128.19 RSUs forfeited (110 ) 141.18 Outstanding at December 31, 2017 1,063 140.46 1.3 $ 143,113

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans We operate a number of defined contribution retirement plans. The costs of these plans are charged to the consolidated statements of income in the period they are incurred. We recorded expense related to our defined contribution plans of $5.5 million , $3.4 million and $2.2 million in 2017 , 2016 and 2015 , respectively. In Ireland, we operate a defined contribution plan in which we contribute up to 8% of an employee’s eligible earnings. We recorded expense of $1.0 million , $0.8 million and $0.6 million in 2017 , 2016 and 2015 , respectively, in connection with the contributions we made under the Irish defined contribution plan. In the U.S., we provide a qualified 401(k) savings plan for our U.S.-based employees. All U.S.-based employees are eligible to participate, provided they meet the requirements of the plan. In 2013, we elected to match certain employee contributions under the 401(k) savings plan. We recorded expense of $3.7 million , $1.9 million and $1.1 million in 2017 , 2016 and 2015 , respectively. In the United Kingdom, or UK, we operate a defined contribution plan in which we contribute up to 12% of an employee’s eligible earnings. We recorded expense of $0.7 million , $0.6 million and $0.4 million in 2017 , 2016 and 2015 , respectively, in connection with contributions we made under the UK defined contribution plan. In France, we accrue for a potential liability which is payable if an employee retires. The accrued liability for France was $0.3 million as of December 31, 2017 and 2016 . In Italy, we accrue for a potential liability which is payable if an employee leaves employment. The accrued liability for Italy was $0.3 million as of December 31, 2017 and 2016 .

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring In 2016 and 2015, we recorded severance costs of $1.5 million for terminated employees in connection with the reorganization of our operations, primarily in France, Italy and the United Kingdom. These one-time termination benefits were recorded over the remaining service period where employees were required to stay through their termination date to receive the benefits and included within cost of product sales and selling, general and administrative expenses in our consolidated statements of income. As of December 31, 2017 , we had incurred total termination benefit costs of $3.0 million in connection with these reorganizations. In addition, we incurred facility closure costs of $0.2 million in 2015 which were recorded within selling, general and administrative expenses in our consolidated statements of income. We completed these restructuring activities in 2017. The following table summarizes the amounts related to restructuring through December 31, 2017 (in thousands): Termination Benefits Facility Closure Costs Total Balance at December 31, 2014 $ 1,823 $ 118 $ 1,941 Expense 1,469 172 1,641 Payments (2,187 ) (290 ) (2,477 ) Balance at December 31, 2015 1,105 — 1,105 Expense 1,516 — 1,516 Payments (2,590 ) — (2,590 ) Balance at December 31, 2016 31 — 31 Expense 14 — 14 Payments (45 ) — (45 ) Balance at December 31, 2017 $ — $ — $ — The balances as of December 31, 2016 and 2015 were included within accrued liabilities in our consolidated balance sheets.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of income before the income tax provision (benefit) and equity in loss of investees were as follows (in thousands): Year Ended December 31, 2017 2016 2015 Ireland $ 77,476 $ 179,570 $ 233,785 United States 271,440 312,904 285,420 Other 92,201 39,972 (83,272 ) Total $ 441,117 $ 532,446 $ 435,933 The following table sets forth the details of the income tax provision (benefit) (in thousands): Year Ended December 31, 2017 2016 2015 Current Ireland $ 28,045 $ 26,420 $ 29,748 United States 135,608 140,061 116,301 Other 14,198 9,918 28,708 Total current tax expense 177,851 176,399 174,757 Deferred, exclusive of other components below Ireland (19,709 ) (7,776 ) (6,655 ) United States (27,559 ) (9,120 ) 332 Other (19,108 ) (13,720 ) (40,532 ) Total deferred, exclusive of other components (66,376 ) (30,616 ) (46,855 ) Deferred, change in tax rates United States (155,679 ) 109 294 Other (3,536 ) (10,656 ) (21,797 ) Total deferred, change in tax rates (159,215 ) (10,547 ) (21,503 ) Total deferred tax benefit (225,591 ) (41,163 ) (68,358 ) Total income tax provision (benefit) $ (47,740 ) $ 135,236 $ 106,399 On December 22, 2017, the U.S. Tax Cuts and Jobs Act, or U.S. Tax Act, was signed into law. The legislation significantly changes U.S. tax law by, among other things, lowering corporate income tax rates, implementing a modified territorial tax system, imposing a one-time transition tax on deemed repatriated earnings of foreign subsidiaries and changing the rules which determine whether a U.S. person is a U.S. shareholder of a controlled foreign corporation, or CFC, for 2017 and onwards. The U.S. Tax Act reduces the U.S. corporate income tax rate from a maximum of 35% to a flat 21% rate, effective January 1, 2018. We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to reverse. As a result of the reduction in the U.S. corporate income tax rate from 35% to 21% under the U.S. Tax Act, we remeasured our ending net deferred tax liabilities as of December 31, 2017 and recognized a $155.1 million tax benefit in our consolidated statement of income in 2017. The U.S. Tax Act provided for a one-time transition tax on the mandatory deemed repatriation of post-1986 undistributed foreign subsidiary earnings and profits through the year ended December 31, 2017 and also changed the rules which determine whether a U.S. person is a U.S. shareholder of a CFC for 2017 and onwards. In relation to these changes, we recognized a provisional $6.3 million of income tax expense in our consolidated statement of income in 2017, which is composed of state current tax expense and deferred tax expense. While the U.S. Tax Act provides for a territorial tax system, beginning in 2018, it includes two new U.S. tax base erosion provisions, the global intangible low-taxed income, or GILTI, provisions and the base-erosion and anti-abuse tax, or BEAT, provisions. The GILTI provisions require us to include in our U.S. income tax return foreign subsidiary earnings in excess of an allowable return on the foreign subsidiary’s tangible assets. Additional analysis is required to determine the application of GILTI for us and no estimate for this has been recorded or policy election made regarding the recognition of GILTI as of and for the year ended December 31, 2017. The BEAT provisions in the U.S. Tax Act eliminates the deduction of certain base-erosion payments made to related foreign corporations, and impose a minimum tax if greater than regular tax. We have not yet fully determined the application of BEAT for us, and it is not effective until 2018. There was no tax impact of BEAT recorded in our consolidated financial statements in 2017. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the U.S. Tax Act. We have recognized the provisional tax impact related to the one-time transition tax on foreign earnings (including the recognition of a provisional valuation allowance), changes to the rules regarding the deductibility of certain executive compensation (including the recognition of a related provisional deferred tax asset of $7.5 million ) and changes to the rules which determine whether a U.S. person is a U.S. shareholder of a CFC, and included these amounts in our consolidated financial statements in 2017. The ultimate impact may differ from these provisional amounts, possibly materially, due to, among other things, additional analysis, changes in interpretations and assumptions we have made, additional regulatory guidance that may be issued, and actions we may take as a result of the U.S. Tax Act. The accounting is expected to be complete when the 2017 U.S. corporate income return is filed in 2018. Our income tax benefit was $47.7 million in 2017 , and our income tax provision was $135.2 million and $106.4 million in 2016 and 2015 , respectively, related to tax arising on income in Ireland, the U.S. and certain other foreign jurisdictions, certain unrecognized tax benefits and various expenses not deductible for income tax purposes. The income tax benefit in 2017 included a provisional net benefit of $148.8 million relating to the impact of the recently enacted U.S Tax Act. The effective tax rates for 2017 , 2016 and 2015 were (10.8)% , 25.4% and 24.4% , respectively. The effective tax rate for 2017 excluding the impact of the U.S. Tax Act was 22.9% . The effective tax rates for 2017 (excluding the impact of the U.S. Tax Act), 2016 and 2015 were higher than the Irish statutory rate of 12.5% , primarily due to income taxable at a rate higher than the Irish statutory rate, unrecognized tax benefits, and various expenses not deductible for income tax purposes, partially offset by originating tax credits, the release of reserves related to unrecognized tax benefits from the expiration of a statute of limitation and the release of a valuation allowance held against certain foreign net operating losses, or NOLs. The decrease in the effective tax rate in 2017 (excluding the impact of the U.S. Tax Act) compared to 2016 was primarily due to the release of a valuation allowance held against certain foreign NOLs and the release of reserves related to unrecognized tax benefits upon the expiration of a statute of limitation, partially offset by a reduction in deductions available in relation to subsidiary equity. The increase in the effective tax rate in 2016 compared to 2015 was primarily due to a decrease in the impact of the reduction in tax rates in certain jurisdictions and a decrease in originating tax credits, partially offset by changes in income mix among the various jurisdictions in which we operate. We are currently paying taxes in Ireland, the U.S. and certain other foreign jurisdictions where we have operations and either all NOLs have been utilized, or are restricted as a result of the Azur Merger. The reconciliation between the statutory income tax rate applied to income before income tax provision (benefit) and equity in loss of investees and our effective income tax rate was as follows: Year Ended December 31, 2017 2016 2015 Statutory income tax rate 12.5 % 12.5 % 12.5 % Impact of U.S. Tax Act (33.7 )% — % — % Foreign income tax rate differential 20.3 % 16.7 % 19.1 % Financing costs (5.6 )% (2.9 )% (0.4 )% Change in unrecognized tax benefits 2.8 % 3.3 % 3.6 % Change in valuation allowance (2.8 )% (0.1 )% (0.6 )% Non-deductible compensation 2.6 % 1.8 % 1.9 % Research and other tax credits (2.6 )% (2.8 )% (3.8 )% Change in estimates (2.1 )% — % (1.0 )% Excess tax benefits from share-based compensation (1.5 )% (1.5 )% — % Deduction on subsidiary equity (0.7 )% (2.4 )% (2.7 )% Change in tax rate (0.4 )% (1.8 )% (4.5 )% Acquisition-related costs — % 2.1 % — % Other 0.4 % 0.5 % 0.3 % Effective income tax rate (10.8 )% 25.4 % 24.4 % Significant components of our net deferred tax assets/(liabilities) were as follows (in thousands): December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 125,966 $ 202,758 Tax credit carryforwards 130,782 114,192 Intangible assets 23,536 15,965 Share-based compensation 23,128 27,522 Accruals 45,088 49,187 Other 92,968 56,739 Total deferred tax assets 441,468 466,363 Valuation allowance (52,144 ) (53,184 ) Net deferred tax assets 389,324 413,179 Deferred tax liabilities: Acquired intangible assets (655,347 ) (910,460 ) Other (82,890 ) (44,392 ) Total deferred tax liabilities (738,237 ) (954,852 ) Net deferred tax liabilities $ (348,913 ) $ (541,673 ) The net change in valuation allowance was a decrease of $1.0 million in 2017 and an increase of $19.2 million and $4.3 million in 2016 and 2015 , respectively. The following table presents the breakdown between deferred tax assets and liabilities (in thousands): Year Ended December 31, 2017 2016 Deferred tax assets $ 34,559 $ 15,060 Deferred tax liabilities (383,472 ) (556,733 ) Net deferred tax liabilities $ (348,913 ) $ (541,673 ) As of December 31, 2017 , we had NOL carryforwards and tax credit carryforwards for U.S. federal income tax purposes of approximately $388.8 million and $117.6 million , respectively, available to reduce future income subject to income taxes. The NOL carryforwards are inclusive of $93.4 million from the EUSA Acquisition in 2012 and $213.6 million from the Celator Acquisition in 2016. The federal NOL carryforwards will expire, if not utilized, in the tax years 2018 to 2035 , and the federal tax credits will expire, if not utilized, in the tax years 2018 to 2037 , with the exception of alternative minimum tax credits, which have no expiration date. In addition, we had approximately $124.4 million of NOL carryforwards and $10.5 million of tax credit carryforwards as of December 31, 2017 available to reduce future taxable income for state income tax purposes. The state NOL carryforwards will expire, if not utilized, in the tax years 2018 to 2034 . In addition, as of December 31, 2017 , there were NOL carryforwards for income tax purposes of approximately $84.0 million and $59.0 million available to reduce future income subject to income taxes in Luxembourg and the United Kingdom, respectively. The NOLs generated in Luxembourg and the United Kingdom have no expiration period. We also had excess foreign tax credits, as of December 31, 2017 , of $4.6 million , which may only be utilized against certain sources of income. The excess foreign tax credits have no expiration period. Utilization of certain of our NOL and tax credit carryforwards in the U.S. is subject to an annual limitation due to the ownership change limitations provided by Sections 382 and 383 of the Internal Revenue Code and similar state provisions. Such an annual limitation may result in the expiration of certain NOLs and tax credits before future utilization. We currently estimate that we have an annual limitation on the utilization of certain acquired federal NOLs and credits of $410.6 million , before tax effect, for 2018, $30.7 million , before tax effect, for 2019 and a combined total of $311.0 million , before tax effect, for 2020 to 2032. In addition, as a result of the Azur Merger, until 2022 we are subject to certain limitations under the Internal Revenue Code in relation to the utilization of U.S. NOLs to offset U.S. taxable income resulting from certain transactions. Valuation allowances require an assessment of both positive and negative evidence when determining whether it is more likely than not that deferred tax assets are recoverable. Such assessment is required on a jurisdiction-by-jurisdiction basis. Our valuation allowance was $52.1 million and $53.2 million as of December 31, 2017 and 2016 , respectively, for certain Irish, U.S. (federal and state) and foreign deferred tax assets which we maintain until sufficient positive evidence exists to support reversal. During 2017, as part of the overall change in valuation allowance, we recognized a net income tax benefit of $6.6 million relating to the net release of a valuation allowance against certain deferred tax assets primarily associated with NOLs, partially offset by the creation of a provisional valuation allowance of $5.9 million against certain deferred tax assets primarily associated with excess foreign tax credits generated during the year as a result of the U.S. Tax Act. The $6.6 million net income tax benefit includes a benefit of $9.1 million relating to the utilization of NOL carryforwards against which a valuation allowance was carried. During 2016, as part of the overall change in valuation allowance, we recognized a net income tax expense of $17.9 million relating to the creation of a valuation allowance against certain deferred tax assets primarily associated with NOLs recognized during the year, partially offset by a release of a valuation allowance due to the impact of the reduction of tax rates in certain jurisdictions and utilization of certain deferred tax assets primarily associated with NOLs. During 2015, as part of the overall change in valuation allowance, we recognized a net income tax expense of $2.4 million relating to the creation of a valuation allowance against certain deferred tax assets primarily associated with NOLs arising during the year, partially offset by a release of a valuation allowance due to the impact of the reduction of tax rates in certain jurisdictions on certain deferred tax assets primarily associated with NOLs. We periodically evaluate the likelihood of the realization of deferred tax assets and will adjust such amounts in light of changing facts and circumstances including, but not limited to, future projections of taxable income, tax legislation, rulings by relevant tax authorities, the progress of tax audits and the regulatory approval of products currently under development. Realization of substantially all the deferred tax assets is dependent on future book income. Temporary differences related to foreign subsidiaries that are considered indefinitely reinvested totaled approximately $1.7 billion and $1.2 billion as of December 31, 2017 and 2016 , respectively. In the event of the distribution of those earnings in the form of dividends, a sale of the subsidiaries, or certain other transactions, we may be liable for income taxes, subject to an adjustment, if any, for foreign tax credits and foreign withholding taxes payable to certain foreign tax authorities. As of December 31, 2017 , it was not practicable to determine the amount of the unrecognized deferred tax liability related to these earnings. We are required to recognize the financial statement effects of a tax position when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. As a result, we have recorded an unrecognized tax benefit for certain tax benefits which we judge may not be sustained upon examination. A reconciliation of our gross unrecognized tax benefits follows (in thousands): December 31, 2017 2016 2015 Balance at the beginning of the year $ 90,910 $ 66,385 $ 40,802 Increases related to current year tax positions 27,875 26,873 23,664 Increases related to prior year tax positions 1,620 1,191 2,833 Decreases related to prior year tax positions (1,075 ) (255 ) (646 ) Lapse of the applicable statute of limitations (13,168 ) (3,284 ) (268 ) Balance at the end of the year $ 106,162 $ 90,910 $ 66,385 The unrecognized tax benefits were included in other non-current liabilities and deferred tax assets, net, in our consolidated balance sheets. Interest related to our unrecognized tax benefits is recorded in the income tax provision in our consolidated statements of income. As of December 31, 2017 and 2016 , our accrued interest and penalties related to unrecognized tax benefits were not significant. Included in the balance of unrecognized tax benefits were potential benefits of $73.5 million and $61.0 million at December 31, 2017 and 2016 , respectively, that, if recognized, would affect the effective tax rate on income. We file income tax returns in multiple tax jurisdictions, the most significant of which are Ireland, the U.S. (both at the federal level and in various state jurisdictions), Italy and France. These jurisdictions have statute of limitations ranging from three to five years. However, in the U.S. (at the federal level and in most states), carryforward tax attributes that were generated in 2013 and earlier may still be adjusted upon examination by the tax authorities. Certain of our subsidiaries are currently under examination by the French tax authorities for the years ended December 31, 2012 and 2013. These examinations may lead to ordinary course adjustments or proposed adjustments to our taxes. In December 2015, we received proposed tax assessment notices from the French tax authorities for 2012 and 2013 relating to certain transfer pricing adjustments. The notices propose additional French tax of approximately $45.9 million , including interest and penalties through the date of the assessment, translated at the foreign exchange rate at December 31, 2017 . We disagree with the proposed assessment and are contesting it vigorously.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	Quarterly Financial Data (Unaudited) The following interim financial information presents our 2017 and 2016 results of operations on a quarterly basis (in thousands, except per share amounts): 2017 March 31 June 30 September 30 December 31 Revenues $ 376,053 $ 394,386 $ 411,855 $ 436,399 Gross margin (1) 348,613 360,983 376,768 404,847 Net income 86,511 105,604 63,526 232,207 Net income per ordinary share, basic 1.44 1.76 1.06 3.87 Net income per ordinary share, diluted 1.41 1.72 1.03 3.79 2016 March 31 June 30 September 30 December 31 Revenues $ 336,010 $ 381,161 $ 374,181 $ 396,621 Gross margin (1) 310,477 355,130 347,310 358,958 Net income 75,812 114,502 89,828 116,689 Net income per ordinary share, basic 1.24 1.89 1.49 1.95 Net income per ordinary share, diluted 1.21 1.85 1.45 1.91 __________________________ (1) Gross margin is computed by subtracting cost of product sales (excluding amortization and impairment of intangible assets) from product sales, net. The interim financial information above includes the following items: • Upfront and milestone payments of $75.0 million and $26.5 million in the third and fourth quarters of 2017, respectively, and $8.8 million and $15.0 million in the first and third quarters of 2016, respectively; • Expenses related to certain legal proceedings and restructuring of $6.0 million in the first quarter of 2017 and $6.1 million in the first quarter of 2016; • Transaction and integration related costs of $2.2 million , $10.8 million and $0.7 million in the second, third and fourth quarters of 2016, respectively; • A loss on extinguishment and modification of debt of $0.6 million in the third quarter of 2016; • A one-time charge of $11.6 million in respect of a contract termination in the fourth quarter of 2016; and • A net benefit of $148.8 million in respect of the impact of the U.S. Tax Act in the fourth quarter of 2017.

Schedule II Valuation and Quali

Schedule II Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Schedule II Valuation and Qualifying Accounts	Schedule II Valuation and Qualifying Accounts (In thousands) Balance at beginning of period Additions charged to costs and expenses Other Additions Deductions Balance at end of period For the year ended December 31, 2017 Allowance for doubtful accounts (1) $ 287 $ 231 $ — $ (122 ) $ 396 Allowance for sales discounts (1) 118 1,087 — (1,102 ) 103 Allowance for chargebacks (1) 4,749 41,941 — (43,027 ) 3,663 Deferred tax asset valuation allowance (2)(3)(4) 53,184 7,509 5,581 (14,130 ) 52,144 For the year ended December 31, 2016 Allowance for doubtful accounts (1) $ 489 $ 168 $ — $ (370 ) $ 287 Allowance for sales discounts (1) 181 1,334 — (1,397 ) 118 Allowance for chargebacks (1) 3,023 41,991 — (40,265 ) 4,749 Deferred tax asset valuation allowance (2)(3)(4) 33,949 19,328 5,544 (5,637 ) 53,184 For the year ended December 31, 2015 Allowance for doubtful accounts (1) $ 530 $ — $ — $ (41 ) $ 489 Allowance for sales discounts (1) 238 2,900 — (2,957 ) 181 Allowance for chargebacks (1) 2,715 39,079 — (38,771 ) 3,023 Deferred tax asset valuation allowance (2)(3)(4) 29,697 5,044 1,888 (2,680 ) 33,949 __________________________ (1) Shown as a reduction of accounts receivable. Charges related to sales discounts and chargebacks are reflected as a reduction of revenue. (2) Additions to the deferred tax asset valuation allowance relate to movements on certain Irish, U.S. (federal and state) and other foreign deferred tax assets where we continue to maintain a valuation allowance until sufficient positive evidence exists to support reversal. (3) Deductions to the deferred tax asset valuation allowance include movements relating to utilization of NOLs and tax credit carryforwards, release in valuation allowance and other movements including adjustments following finalization of tax returns. (4) Other additions to the deferred tax asset valuation allowance relate to currency translation adjustments recorded directly in other comprehensive income and a valuation allowance recognized in 2016 on purchase accounting.

Summary of Significant Accoun31

Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP, and include the accounts of Jazz Pharmaceuticals plc and our subsidiaries and intercompany transactions and balances have been eliminated. Our consolidated financial statements include the results of operations of businesses we have acquired from the date of each acquisition for the applicable reporting periods.
Significant Risks and Uncertainties	Significant Risks and Uncertainties Our financial results are significantly influenced by sales of Xyrem. Our ability to maintain or increase Xyrem product sales is subject to a number of risks and uncertainties, including, without limitation, the potential introduction of a generic version of Xyrem before the entry dates specified in, or on terms different from those contemplated by, our settlements with companies seeking to obtain or that have obtained regulatory approval to market generic versions of Xyrem; the potential introduction of new products that compete with Xyrem; ongoing patent litigation and related proceedings; changed or increased regulatory restrictions, including with respect to the Xyrem risk evaluation and mitigation strategy, or REMS; any increase in pricing pressure from, changes in policies by, or restrictions on reimbursement imposed by, third party payors; operational disruptions at the Xyrem central pharmacy; and continued acceptance of Xyrem by physicians and patients. In addition to risks related specifically to Xyrem, we are subject to other challenges and risks specific to our business and our ability to execute on our strategy, as well as risks and uncertainties common to companies in the pharmaceutical industry with development and commercial operations, including, without limitation, risks and uncertainties associated with: effectively commercializing our other products and product candidates; pharmaceutical product development and the inherent uncertainty of clinical success; the regulatory approval process; the challenges of protecting and enhancing our intellectual property rights; our dependence on sole source suppliers for most of our products, including the risk of delays or problems in the supply or manufacture of our products and product candidates; competition; complying with applicable regulatory requirements; changes in healthcare laws and policy and related reforms; government investigations and other actions; obtaining and maintaining appropriate pricing and reimbursement for our products; business combination or product or product candidate acquisition transactions; and possible restrictions on our ability and flexibility to pursue certain future opportunities as a result of our substantial outstanding debt obligations.
Business Acquisitions	Business Acquisitions Our consolidated financial statements include the results of operations of an acquired business from the date of acquisition. We account for acquired businesses using the acquisition method of accounting. The acquisition method of accounting for acquired businesses requires, among other things, that assets acquired, liabilities assumed and any noncontrolling interests in the acquired business be recognized at their estimated fair values as of the acquisition date, with limited exceptions, and that the fair value of acquired in-process research and development, or IPR&D, be recorded on the balance sheet. Also, transaction costs are expensed as incurred. Any excess of the acquisition consideration over the assigned values of the net assets acquired is recorded as goodwill. Contingent consideration is included within the acquisition cost and is recognized at its fair value on the acquisition date. A liability resulting from contingent consideration is remeasured to fair value at each reporting date until the contingency is resolved and changes in fair value are recognized in earnings.
Concentrations of Risk	Concentrations of Risk Financial instruments that potentially subject us to concentrations of credit risk consist of cash, cash equivalents, investments and derivative contracts. Our investment policy permits investments in U.S. federal government and federal agency securities, corporate bonds or commercial paper issued by U.S. corporations, money market instruments, certain qualifying money market mutual funds, certain repurchase agreements, and tax-exempt obligations of U.S. states, agencies and municipalities and places restrictions on credit ratings, maturities, and concentration by type and issuer. We are exposed to credit risk in the event of a default by the financial institutions holding our cash, cash equivalents and investments to the extent recorded on the balance sheet. We manage our foreign currency transaction risk and interest rate risk within specified guidelines through the use of derivatives. All of our derivative instruments are utilized for risk management purposes, and we do not use derivatives for speculative trading purposes. As of December 31, 2017 , we had foreign exchange forward contracts with notional amounts totaling $98.7 million . As of December 31, 2017 , the net asset fair value of outstanding foreign exchange forward contracts was $10.5 million . As of December 31, 2017 , we had interest rate swap contracts with notional amounts totaling $300.0 million . These outstanding interest rate swap contracts had a net asset fair value of $1.7 million as of December 31, 2017 . The counterparties to these contracts are large multinational commercial banks, and we believe the risk of nonperformance is not material. We are also subject to credit risk from our accounts receivable related to our product sales. We monitor our exposure within accounts receivable and record a reserve against uncollectible accounts receivable as necessary. We extend credit to pharmaceutical wholesale distributors and specialty pharmaceutical distribution companies, primarily in the U.S., and to other international distributors and hospitals. Customer creditworthiness is monitored and collateral is not required. We monitor deteriorating economic conditions in certain European countries which may result in variability of the timing of cash receipts and an increase in the average length of time that it takes to collect accounts receivable outstanding. Historically, we have not experienced significant credit losses on our accounts receivable. As of December 31, 2017 , five customers accounted for 90% of gross accounts receivable including Express Scripts Specialty Distribution Services, Inc. and its affiliates, or Express Scripts, which accounted for 71% of gross accounts receivable, and McKesson Corporation and affiliates, or McKesson, which accounted for 15% of gross accounts receivable. As of December 31, 2016 , five customers accounted for 90% of gross accounts receivable including Express Scripts, which accounted for 73% of gross accounts receivable, and McKesson, which accounted for 13% of gross accounts receivable. We depend on single source suppliers for most of our products, product candidates and their active pharmaceutical ingredients, or APIs. With respect to Xyrem, the API is manufactured for us by a single source supplier and the finished product is manufactured both by us in our facility in Athlone, Ireland and by our U.S.-based Xyrem supplier.
Cash Equivalents and Investments	Cash Equivalents and Investments We consider all highly liquid investments, readily convertible to cash, that mature within three months or less from date of purchase to be cash equivalents. Investments consist of time deposits with initial maturities of greater than three months. Collectively, cash equivalents and investments are considered available-for-sale and are recorded at fair value. Unrealized gains and losses, net of tax, are recorded in accumulated other comprehensive loss in shareholders’ equity. We use the specific-identification method for calculating realized gains and losses on securities sold. Realized gains and losses and declines in value judged to be other than temporary on investments are included in interest expense, net in the consolidated statements of income.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities We record the fair value of derivative instruments as either assets or liabilities on the consolidated balance sheets. Changes in the fair value of derivative instruments are recorded each period in current earnings or other comprehensive income (loss), depending on whether a derivative instrument is designated as part of a hedging transaction and, if it is, the type of hedging transaction. For a derivative to qualify as a hedge at inception and throughout the hedged period, we formally document the nature and relationships between the hedging instruments and hedged item. We assess, both at inception and on an on-going basis, whether the derivative instruments that are used in cash flow hedging transactions are highly effective in offsetting the changes in cash flows of hedged items. We assess hedge ineffectiveness on a quarterly basis and record the gain or loss related to the ineffective portion of derivative instruments, if any, to current earnings. If we determine that a forecasted transaction is no longer probable of occurring, we discontinue hedge accounting and any related unrealized gain or loss on the derivative instrument is recognized in current earnings. Derivatives that are not designated and do not qualify as hedges are adjusted to fair value through current earnings.
Inventories	Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method for all inventories. Our policy is to write down inventory that has become obsolete, inventory that has a cost basis in excess of its expected net realizable value and inventory in excess of expected requirements. The estimate of excess quantities is subjective and primarily dependent on our estimates of future demand for a particular product. If our estimate of future demand changes, we consider the impact on the reserve for excess inventory and adjust the reserve as required. Increases in the reserve are recorded as charges in cost of product sales. For product candidates that have not been approved by the FDA, inventory used in clinical trials is expensed at the time of production and recorded as research and development expense. For products that have been approved by the FDA, inventory used in clinical trials is expensed at the time the inventory is packaged for the clinical trial. Prior to receiving FDA approval, costs related to purchases of the API and the manufacturing of the product candidate are recorded as research and development expense. All direct manufacturing costs incurred after approval are capitalized into inventory.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Estimated useful lives are as follows: Buildings 40 years Manufacturing equipment and machinery 5-10 years Computer software and equipment 3 years Furniture and fixtures 5 years Leasehold improvements and the build-to-suit facility are amortized over the shorter of the noncancelable term of our leases or their economic useful lives. Maintenance and repairs are expensed as incurred.
Operating Leases and Financing Obligations	Operating Leases and Financing Obligations We recognize rent expense under operating leases on a straight-line basis over the term of the lease with the difference between the expense and cash payments recorded as deferred rent on the consolidated balance sheets. For certain build-to-suit lease arrangements where we have concluded that we are the “deemed owner” of the building, for accounting purposes only, during the construction period, we are required to record an asset with a corresponding financing obligation for the construction costs incurred by the landlord. The financing obligation is recorded as a component of other non-current liabilities in the consolidated balance sheets. We increase the asset and financing obligation as additional building costs are incurred by the landlord during the construction period. Once construction is complete, we evaluate whether the asset qualifies for sale-leaseback accounting treatment. If the lease meets the sale-leaseback criteria, we remove the asset and the related liability from the consolidated balance sheets and treat the lease as either an operating or capital lease based on an assessment of the accounting guidance. If the arrangement does not qualify for sale-leaseback treatment, we reduce the financing obligation over the lease term as payments are made and depreciate the asset over its estimated useful life or lease term, whichever is shorter. Future lease payments associated with build-to-suit leases where we are the deemed owner are allocated between the land and building components. The portion of the lease payments allocated to the land is treated for accounting purposes as operating lease payments, and therefore is recorded as rent expense in the consolidated statements of income. The portion of the lease payments allocated to the building is further bifurcated into a portion allocated to interest expense and a portion allocated to reduce the build-to-suit financing obligation.
Goodwill, Acquired In-Process Research and Development, and Intangible Assets	Goodwill Goodwill represents the excess of the acquisition consideration over the fair value of assets acquired and liabilities assumed. We have determined that we operate in a single segment and have a single reporting unit associated with the development and commercialization of pharmaceutical products. The annual test for goodwill impairment is a two-step process. The first step is a comparison of the fair value of the reporting unit with its carrying amount, including goodwill. If this step indicates impairment, then, in the second step, the loss is measured as the excess of recorded goodwill over its implied fair value. Implied fair value is the excess of the fair value of the reporting unit over the fair value of all identified assets and liabilities. We test goodwill for impairment annually in October and when events or changes in circumstances indicate that the carrying value may not be recoverable. Acquired In-Process Research and Development The initial costs of rights to IPR&D projects acquired in an asset acquisition are expensed as IPR&D unless the project has an alternative future use. The fair value of IPR&D projects acquired in a business combination are capitalized and accounted for as indefinite-lived intangible assets until the underlying project receives regulatory approval, at which point the intangible asset will be accounted for as a finite-lived intangible asset, or discontinued, at which point the intangible asset will be written off. Development costs incurred after an acquisition are expensed as incurred. Intangible Assets Intangible assets with finite useful lives consist primarily of purchased developed technology and are amortized on a straight-line basis over their estimated useful lives, which range from two to 18 years. The estimated useful lives associated with finite-lived intangible assets are consistent with the estimated lives of the associated products and may be modified when circumstances warrant. Such assets are reviewed for impairment when events or circumstances indicate that the carrying value of an asset may not be recoverable. An impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of an asset and its eventual disposition are less than its carrying amount. The amount of any impairment is measured as the difference between the carrying amount and the fair value of the impaired asset.
Revenue Recognition	Revenue Recognition Revenues are recognized when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed and determinable and collection is reasonably assured. Product Sales, Net Product sales revenue is recognized when title has transferred to the customer and the customer has assumed the risks and rewards of ownership, which is typically on delivery to the customer or, in the case of products that are subject to consignment agreements, when the customer removes product from our consigned inventory location for shipment directly to a patient. Revenue from sales transactions where the buyer has the right to return the product is recognized at the time of sale only if (i) the seller’s price to the buyer is substantially fixed or determinable at the date of sale, (ii) the buyer has paid the seller, or the buyer is obligated to pay the seller and the obligation is not contingent on resale of the product, (iii) the buyer’s obligation to the seller would not be changed in the event of theft or physical destruction or damage of the product, (iv) the buyer acquiring the product for resale has economic substance apart from that provided by the seller, (v) the seller does not have significant obligations for future performance to directly bring about resale of the product by the buyer, and (vi) the amount of future returns can be reasonably estimated. Revenues from sales of products are recorded net of estimated allowances for returns, specialty distributor fees, wholesaler fees, prompt payment discounts, government rebates, government chargebacks, coupon programs and rebates under managed care plans. Provisions for returns, specialty distributor fees, wholesaler fees, government rebates, coupon programs and rebates under managed care plans are included within current liabilities in our consolidated balance sheets. Provisions for government chargebacks and prompt payment discounts are generally shown as a reduction in accounts receivable. Calculating certain of these items involves estimates and judgments based on sales or invoice data, contractual terms, historical utilization rates, new information regarding changes in these programs’ regulations and guidelines that would impact the amount of the actual rebates, our expectations regarding future utilization rates for these programs and channel inventory data. Adjustments to estimates for these allowances have not been material. Royalties and Contract Revenues We receive royalties from third parties based on sales of our products under licensing and distribution arrangements. For those arrangements where royalties are reasonably estimable, we recognize revenues based on estimates of royalties earned during the applicable period, and adjust for differences between the estimated and actual royalties in the following quarter. Historically, these adjustments have not been significant. Our contract revenues consist of fees and milestone payments. Non-refundable fees where we have no continuing performance obligations are recognized as revenues when there is persuasive evidence of an arrangement and collection is reasonably assured. In situations where we have continuing performance obligations, non-refundable fees are deferred and are recognized ratably over our projected performance period. We recognize at-risk milestone payments, which are typically related to regulatory, commercial or other achievements by us or our licensees and distributors, as revenues when the milestone is accomplished and collection is reasonably assured. Sales-based milestone payments are typically payments made to us that are triggered when aggregate net sales of a product by a collaborator for a specified period (for example, an annual period) reach an agreed upon threshold amount. We recognize sales-based milestone payments from a collaborator when the event which triggers the obligation of payment has occurred, there is no further obligation on our part in connection with the payment, and collection is reasonably assured. Refundable fees are deferred and recognized as revenues upon the later of when they become nonrefundable or when our performance obligations are completed.
Cost of Product Sales	Cost of Product Sales Cost of product sales includes manufacturing and distribution costs, the cost of drug substance, royalties due to third parties on product sales, product liability and cargo insurance, FDA user fees, freight, shipping, handling and storage costs and salaries and related costs of employees involved with production
Research and Development	Research and Development Research and development expenses consist primarily of costs related to clinical studies and outside services, personnel expenses and other research and development costs, including milestone payments incurred prior to regulatory approval of products. Clinical study and outside services costs relate primarily to services performed by clinical research organizations, clinical studies performed at clinical sites, materials and supplies, and other third party fees. Personnel expenses relate primarily to salaries, benefits and share-based compensation. Other research and development expenses primarily include overhead allocations consisting of various support and facilities-related costs. Research and development costs are expensed as incurred. For product candidates that have not been approved by the FDA, inventory used in clinical trials is expensed at the time of production and recorded as research and development expense. For products that have been approved by the FDA, inventory used in clinical trials is expensed at the time the inventory is packaged for the trial.
Advertising Expenses	Advertising Expenses We expense the costs of advertising, including promotional expenses, as incurred.
Income Taxes	Income Taxes We use the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between the financial statement carrying amount and the tax basis of assets and liabilities and are measured using enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is provided when it is more-likely-than-not that some portion or all of a deferred tax asset will not be realized. We recognize the benefits of a tax position if it is “more-likely-than-not” of being sustained. A recognized tax benefit is then measured at the largest amount of benefit that is greater than fifty percent likely of being realized upon settlement. Interest and penalties related to unrecognized tax benefits are included in the income tax provision and classified with the related liability on the consolidated balance sheets.
Foreign Currency	Foreign Currency Our functional and reporting currency is the U.S. dollar. The assets and liabilities of our subsidiaries that have a functional currency other than the U.S. dollar are translated into U.S. dollars at the exchange rate prevailing at the balance sheet date with the results of operations of subsidiaries translated at the average exchange rate for the reporting period. The cumulative foreign currency translation adjustment is recorded as a component of accumulated other comprehensive income (loss) in shareholders’ equity. Transactions in foreign currencies are translated into the functional currency of the relevant subsidiary at the rate of exchange prevailing at the date of the transaction. Any monetary assets and liabilities arising from these transactions are translated into the relevant functional currency at exchange rates prevailing at the balance sheet date or on settlement. Resulting gains and losses are recorded in foreign exchange gain (loss) in our consolidated statements of income.
Deferred Financing Costs	Deferred Financing Costs Deferred financing costs are reported at cost, less accumulated amortization and are presented in the consolidated balance sheets as a direct deduction from the carrying value of the associated debt, with the exception of deferred financing costs associated with revolving-debt arrangements which are presented as assets. The related amortization expense is included in interest expense, net in our consolidated statements of income.
Contingencies	Contingencies From time to time, we may become involved in claims and other legal matters arising in the ordinary course of business. We record accruals for loss contingencies to the extent that we conclude that it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. Legal fees and other expenses related to litigation are expensed as incurred and included in selling, general and administrative expenses.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures in the consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. Actual results could differ materially from those estimates.
Net Income per Ordinary Share	Net Income per Ordinary Share Basic net income per ordinary share attributable to Jazz Pharmaceuticals plc is based on the weighted-average number of ordinary shares outstanding. Diluted net income per ordinary share attributable to Jazz Pharmaceuticals plc is based on the weighted-average number of ordinary shares outstanding and potentially dilutive ordinary shares outstanding.
Share-Based Compensation	Share-Based Compensation We account for compensation cost for all share-based awards at fair value on the date of grant. The fair value is recognized as expense over the service period, net of estimated forfeitures, using the straight-line method. The estimation of share-based awards that will ultimately vest requires judgment, and, to the extent actual results or updated estimates differ from current estimates, such amounts will be recorded as a cumulative adjustment in the period estimates are revised. We primarily consider historical experience when estimating expected forfeitures.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2017, the Financial Accounting Standards Board, or FASB, issued ASU No. 2017-12, “Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities”. ASU No. 2017-12 amends and simplifies existing guidance in order to allow companies to more accurately present the economic effects of risk management activities in their financial statements. ASU No. 2017-12 is effective for reporting periods beginning after December 15, 2018, with early adoption permitted. We have elected to early adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In January 2017, the FASB, issued ASU No. 2017-04, “Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment” which simplifies the accounting for goodwill impairment by eliminating Step 2 of the current goodwill impairment test. Goodwill impairment will now be the amount by which the reporting unit’s carrying value exceeds its fair value, limited to the carrying value of the goodwill. The standard is effective for us beginning January 1, 2020. Early adoption is permitted for any impairment tests performed after January 1, 2017. The new guidance is not expected to have a material impact on our consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” which provides clarification on the definition of a business and adds guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018. The future impact of ASU No. 2017-01 will be dependent upon the nature of our future acquisition or disposition transactions, if any. In October 2016, the FASB issued ASU No. 2016-16, “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory” which requires an entity to recognize the income tax consequences of an intra-entity asset transfer, other than an intra-entity asset transfer of inventory, when the transfer occurs. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments”. ASU 2016-15 addresses how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The standard is effective for us beginning January 1, 2018. Early adoption is permitted. We will adopt this standard beginning in the first quarter of 2018 and do not expect adoption to have a material impact on our consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842)”. Under the new guidance, lessees will be required to recognize a right-of-use asset, which represents the lessee’s right to use, or control the use of, a specified asset for the lease term, and a corresponding lease liability, which represents the lessee’s obligation to make lease payments under a lease, measured on a discounted basis. ASU No. 2016-02 is effective beginning January 1, 2019 and early adoption is permitted. ASU No. 2016-02 must be adopted on a modified retrospective transition basis for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the consolidated financial statements. The adoption of ASU No. 2016-02 will result in a significant increase in our consolidated balance sheet for right-of-use assets and lease liabilities. While we are continuing to assess all potential impacts of the standard, we currently believe the most significant impact relates to our accounting for the lease agreements we entered into in January 2015 and September 2017 to lease office space located in Palo Alto, California in buildings constructed or to be constructed by the landlord, which are accounted for as build-to-suit arrangements under existing accounting standards, and the lease agreement we entered into in August 2016 for office space in Dublin, Ireland. The future minimum lease payments under these leases at December 31, 2017 was $215.2 million . In May 2014, the FASB issued ASU No. 2014-09, “Revenue from Contracts with Customers”. The standard states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this, an entity will need to identify the contract with a customer; identify the separate performance obligations in the contract; determine the transaction price; allocate the transaction price to the separate performance obligations in the contract; and recognize revenue when (or as) the entity satisfies each performance obligation. In August 2015, the FASB issued ASU No. 2015-14, “Revenue from Contracts with Customers: Deferral of the Effective Date”, which deferred the effective date of ASU No. 2014-09. ASU No. 2014-09 was effective for us beginning January 1, 2018 and could be adopted on a full retrospective basis or on a modified retrospective basis. In March 2016, the FASB issued ASU No. 2016-08, “Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations”, which clarifies the implementation guidance on principal versus agent considerations. In April 2016, the FASB issued ASU No. 2016-10, “Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing”, which clarifies certain aspects of identifying performance obligations and licensing implementation guidance. In May 2016, the FASB issued ASU No. 2016-12, “Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients” related to disclosures of remaining performance obligations, as well as other amendments to guidance on collectability, non-cash consideration and the presentation of sales and other similar taxes collected from customers. We will adopt ASU No. 2014-09 beginning in the first quarter of 2018 on a modified retrospective basis. The adoption of ASU No. 2014-09 is not expected to have a material impact on our results of operations and financial position as the timing of revenue recognition for product sales, net, which is our primary revenue stream, is not expected to change. On adoption of the new standard, we expect to reclassify approximately $2 million of deferred revenue, related to historical upfront payments received under a licensing arrangement, directly to retained earnings. We will be required to provide additional revenue-related disclosures in the notes to the consolidated financial statements commencing with our consolidated financial statements for the quarter ending March 31, 2018. We have concluded that no significant changes are required to our existing internal controls, systems and processes in order to support revenue recognition and the additional revenue-related disclosures under the new standard.

Summary of Significant Accoun32

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Schedule of property and equipment	Estimated useful lives are as follows: Buildings 40 years Manufacturing equipment and machinery 5-10 years Computer software and equipment 3 years Furniture and fixtures 5 years Property and equipment consisted of the following (in thousands): December 31, 2017 2016 Build-to-suit facility $ 51,721 $ — Land and buildings 46,729 46,033 Leasehold improvements 28,779 9,328 Manufacturing equipment and machinery 23,586 19,596 Construction-in-progress 21,738 33,427 Computer software 19,969 17,832 Computer equipment 12,814 10,980 Furniture and fixtures 5,947 2,436 Subtotal 211,283 139,632 Less accumulated depreciation and amortization (41,203 ) (32,142 ) Property and equipment, net $ 170,080 $ 107,490
Schedule of net income per ordinary share	Basic and diluted net income per ordinary share attributable to Jazz Pharmaceuticals plc were computed as follows (in thousands, except per share amounts): Year Ended December 31, 2017 2016 2015 Numerator: Net income attributable to Jazz Pharmaceuticals plc $ 487,848 $ 396,831 $ 329,535 Denominator: Weighted-average ordinary shares used in per share calculations - basic 60,018 60,500 61,232 Dilutive effect of employee equity incentive and purchase plans 1,299 1,370 1,804 Weighted-average ordinary shares used in per share calculations - diluted 61,317 61,870 63,036 Net income per ordinary share : Basic $ 8.13 $ 6.56 $ 5.38 Diluted $ 7.96 $ 6.41 $ 5.23
Schedule of computation of diluted net income (loss) per share having anti-dilutive effect	The following table represents the weighted-average ordinary shares that were excluded from the computation of diluted net income attributable to Jazz Pharmaceuticals plc per ordinary share for the years presented because including them would have an anti-dilutive effect (in thousands): Year Ended December 31, 2017 2016 2015 Exchangeable Senior Notes 3,805 2,878 2,878 Options to purchase ordinary shares and RSUs 3,319 3,010 1,609 Ordinary shares under ESPP 14 93 —

Business Combination, Asset A33

Business Combination, Asset Acquisitions, and Disposition (Tables)	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Summary of assets and liabilities assumed in acquisition	The fair values of assets acquired and liabilities assumed at the closing date of the Celator Acquisition are summarized below (in thousands): Cash and cash equivalents $ 26,137 Other receivables 386 Prepaid expenses and deposits 151 Property and equipment 767 Intangible assets 1,811,250 Goodwill 252,825 Other non-current assets 43 Accrued liabilities (19,076 ) Deferred tax liability, net, non-current (542,901 ) Other non-current liabilities (1,002 ) Total acquisition consideration - cash paid $ 1,528,580
Summary of pro forma financial information	The unaudited pro forma results do not assume any operating efficiencies as a result of the consolidation of operations and are as follows (in thousands, except per share data): Year Ended December 31, 2016 2015 Revenues $ 1,488,118 $ 1,326,246 Net income attributable to Jazz Pharmaceuticals plc $ 386,342 $ 283,113 Net income attributable to Jazz Pharmaceuticals plc per ordinary share - basic $ 6.39 $ 4.62 Net income attributable to Jazz Pharmaceuticals plc per ordinary share - diluted $ 6.24 $ 4.49

Cash and Available-for-Sale S34

Cash and Available-for-Sale Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents and Investments	Cash and cash equivalents and investments consisted of the following (in thousands): December 31, 2017 Amortized Gross Gross Estimated Cash and Cash Equivalents Investments Cash $ 225,235 $ — $ — $ 225,235 $ 225,235 $ — Time deposits 235,000 — — 235,000 20,000 215,000 Money market funds 140,800 — — 140,800 140,800 — Totals $ 601,035 $ — $ — $ 601,035 $ 386,035 $ 215,000 December 31, 2016 Amortized Gross Gross Estimated Cash and Cash Investments Cash $ 215,963 $ — $ — $ 215,963 $ 215,963 $ — Time deposits 210,000 — — 210,000 150,000 60,000 Totals $ 425,963 $ — $ — $ 425,963 $ 365,963 $ 60,000

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table summarizes, by major security type, our available-for-sale securities and derivative contracts that were measured at fair value on a recurring basis and were categorized using the fair value hierarchy (in thousands): December 31, 2017 December 31, 2016 Quoted Significant Total Significant Total Assets: Available-for-sale securities: Time deposits $ — $ 235,000 $ 235,000 $ 210,000 $ 210,000 Money market funds 140,800 — 140,800 — — Interest rate contracts — 2,138 2,138 — — Foreign exchange forward contracts — 15,495 15,495 — — Totals $ 140,800 $ 252,633 $ 393,433 $ 210,000 $ 210,000 Liabilities: Interest rate contracts $ — $ 392 $ 392 $ — $ — Foreign exchange forward contracts — 5,017 5,017 — — Totals $ — $ 5,409 $ 5,409 $ — $ —

Derivatives and Hedging Activ36

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of gains (losses) on derivative instruments	The impact on accumulated other comprehensive loss and earnings from derivative instruments that qualified as cash flow hedges was as follows (in thousands): Year Ended December 31, 2017 2016 Loss recognized in accumulated other comprehensive loss, net of tax $ (213 ) $ — Loss reclassified from accumulated other comprehensive loss to interest expense, net of tax $ 1,695 $ —
Schedule of the fair value of outstanding derivatives	The following table summarizes the fair value of outstanding derivatives as of December 31, 2017 (in thousands): December 31, 2017 Asset Derivatives Liability Derivatives Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments: Interest rate contracts Other non-current assets $ 2,138 Accrued liabilities $ 392 Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets 15,495 Accrued liabilities 5,017 Total fair value of derivative instruments $ 17,633 $ 5,409
Schedule of offsetting assets	The following table summarizes the potential effect on our consolidated balance sheets of offsetting our interest rate contracts and foreign exchange forward contracts subject to such provisions (in thousands): December 31, 2017 Gross Amounts of Recognized Assets/Liabilities Gross Amounts Offset in the Consolidated Balance Sheet Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Description Derivative Financial Instruments Cash Collateral Received (Pledged) Net Amount Derivative assets $ 1,639 $ — $ 1,639 $ (875 ) $ — $ 764 Derivative liabilities $ (875 ) $ — $ (875 ) $ 875 $ — $ —
Schedule of offsetting liabilities	The following table summarizes the potential effect on our consolidated balance sheets of offsetting our interest rate contracts and foreign exchange forward contracts subject to such provisions (in thousands): December 31, 2017 Gross Amounts of Recognized Assets/Liabilities Gross Amounts Offset in the Consolidated Balance Sheet Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Description Derivative Financial Instruments Cash Collateral Received (Pledged) Net Amount Derivative assets $ 1,639 $ — $ 1,639 $ (875 ) $ — $ 764 Derivative liabilities $ (875 ) $ — $ (875 ) $ 875 $ — $ —

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Components of inventories	Inventories consisted of the following (in thousands): December 31, 2017 2016 Raw materials $ 3,542 $ 1,547 Work in process 15,692 18,689 Finished goods 24,011 13,815 Total inventories $ 43,245 $ 34,051

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of property and equipment	Estimated useful lives are as follows: Buildings 40 years Manufacturing equipment and machinery 5-10 years Computer software and equipment 3 years Furniture and fixtures 5 years Property and equipment consisted of the following (in thousands): December 31, 2017 2016 Build-to-suit facility $ 51,721 $ — Land and buildings 46,729 46,033 Leasehold improvements 28,779 9,328 Manufacturing equipment and machinery 23,586 19,596 Construction-in-progress 21,738 33,427 Computer software 19,969 17,832 Computer equipment 12,814 10,980 Furniture and fixtures 5,947 2,436 Subtotal 211,283 139,632 Less accumulated depreciation and amortization (41,203 ) (32,142 ) Property and equipment, net $ 170,080 $ 107,490

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of gross carrying amount of goodwill	The gross carrying amount of goodwill was as follows (in thousands): Balance at December 31, 2016 $ 893,810 Foreign exchange 53,727 Balance at December 31, 2017 $ 947,537
Schedule of gross carrying amounts and net book values of intangible assets	The gross carrying amounts and net book values of our intangible assets were as follows (in thousands): December 31, 2017 December 31, 2016 Remaining Gross Accumulated Net Book Gross Accumulated Net Book Acquired developed technologies 14.9 $ 3,392,832 $ (562,473 ) $ 2,830,359 $ 1,477,618 $ (410,523 ) $ 1,067,095 Manufacturing contracts 0.1 12,824 (12,634 ) 190 11,278 (8,292 ) 2,986 Trademarks — 2,910 (2,910 ) — 2,872 (2,872 ) — Total finite-lived intangible assets 3,408,566 (578,017 ) 2,830,549 1,491,768 (421,687 ) 1,070,081 Acquired IPR&D assets 148,578 — 148,578 1,941,920 — 1,941,920 Total intangible assets $ 3,557,144 $ (578,017 ) $ 2,979,127 $ 3,433,688 $ (421,687 ) $ 3,012,001
Schedule of estimated future amortization costs	Based on finite-lived intangible assets recorded as of December 31, 2017 , and assuming the underlying assets will not be impaired and that we will not change the expected lives of the assets, future amortization expenses were estimated as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2018 $ 209,912 2019 209,674 2020 206,706 2021 205,655 2022 204,922 Thereafter 1,793,680 Total $ 2,830,549

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Schedule of accrued liabilities	Accrued liabilities consisted of the following (in thousands): December 31, 2017 2016 Rebates and other sales deductions $ 81,368 $ 72,344 Employee compensation and benefits 54,930 43,363 Royalties 8,058 11,643 Accrued interest 7,297 5,179 Derivative instrument liabilities 5,409 — Sales returns reserve 3,651 4,366 Professional fees 3,213 4,596 Selling and marketing accruals 3,189 3,924 Inventory-related accruals 3,002 3,350 Accrued construction-in-progress 2,827 1,597 Clinical trial accruals 2,181 10,139 Accrued contract termination fees — 11,612 Other 23,654 21,155 Total accrued liabilities $ 198,779 $ 193,268

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of long-term debt	The following table summarizes the carrying amount of our indebtedness (in thousands): December 31, 2017 2016 2021 Notes $ 575,000 $ 575,000 Unamortized discount and debt issuance costs on 2021 Notes (81,627 ) (101,094 ) 2021 Notes, net 493,373 473,906 2024 Notes 575,000 — Unamortized discount and debt issuance costs on 2024 Notes (158,680 ) — 2024 Notes, net 416,320 — Term loan 671,345 705,719 Borrowings under revolving credit facility — 850,000 Total debt 1,581,038 2,029,625 Less current portion 40,605 36,094 Total long-term debt $ 1,540,433 $ 1,993,531
Schedule of maturities of long-term debt	Scheduled maturities with respect to our long-term debt are as follows (in thousands): Year Ending December 31, Scheduled Long-Term Debt Maturities 2018 $ 40,605 2019 58,652 2020 76,700 2021 1,075,801 Thereafter 575,000 Total $ 1,826,758

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum lease payments under noncancelable operating leases	Future minimum lease payments under our noncancelable facility leases as of December 31, 2017 , were as follows (in thousands): Year Ending December 31, Lease Payments 2018 $ 6,297 2019 9,142 2020 14,392 2021 14,824 2022 15,269 Thereafter 135,473 Total $ 195,397 Future minimum lease payments under our noncancelable operating leases as of December 31, 2017 , were as follows (in thousands): Year ending December 31, Lease Payments 2018 $ 9,102 2019 8,166 2020 6,111 2021 5,212 2022 5,007 Thereafter 12,753 Total $ 46,351
Schedule of lease expense under operating leases	Lease expense under our operating leases was as follows (in thousands): Year Ended December 31, 2017 2016 2015 Lease expense $ 14,982 $ 11,600 $ 10,479

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of authorized but unissued ordinary shares	We had reserved the following shares of authorized but unissued ordinary shares (in thousands): December 31, 2017 2011 Equity Incentive Plan 16,026 Amended and Restated 2007 Non-Employee Directors Stock Award Plan 481 2007 Employee Stock Purchase Plan 339 Amended and Restated Directors Deferred Compensation Plan 178 2007 Equity Incentive Plan 17 Total 17,041

Comprehensive Income (Loss) (Ta

Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Components of accumulated other comprehensive loss	The components of accumulated other comprehensive loss as of December 31, 2017 and December 31, 2016 were as follows (in thousands): Net Unrealized Foreign Total Balance at December 31, 2016 $ — $ (317,333 ) $ (317,333 ) Other comprehensive income (loss) before reclassifications (213 ) 174,973 174,760 Amounts reclassified from accumulated other comprehensive loss 1,695 — 1,695 Other comprehensive income, net 1,482 174,973 176,455 Balance at December 31, 2017 $ 1,482 $ (142,360 ) $ (140,878 )

Segment and Other Information (

Segment and Other Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Summary of total revenues	The following table presents a summary of total revenues (in thousands): Year Ended December 31, 2017 2016 2015 Xyrem $ 1,186,699 $ 1,107,616 $ 955,187 Erwinaze/Erwinase 197,340 200,678 203,261 Defitelio/defibrotide 133,650 108,952 70,731 Vyxeos 33,790 — — Prialt ® (ziconotide) intrathecal infusion 27,361 29,120 26,440 Other 22,559 30,895 61,200 Product sales, net 1,601,399 1,477,261 1,316,819 Royalties and contract revenues 17,294 10,712 7,984 Total revenues $ 1,618,693 $ 1,487,973 $ 1,324,803
Summary of total revenues attributed to geographic sources	The following table presents a summary of total revenues attributed to geographic sources (in thousands): Year Ended December 31, 2017 2016 2015 United States $ 1,463,457 $ 1,354,921 $ 1,192,879 Europe 122,789 106,146 103,614 All other 32,447 26,906 28,310 Total revenues $ 1,618,693 $ 1,487,973 $ 1,324,803
Summary of revenues from customers representing more than 10% of total revenues	The following table presents a summary of the percentage of total revenues from customers that represented more than 10% of our total revenues: Year Ended December 31, 2017 2016 2015 Express Scripts 73 % 74 % 72 % McKesson 16 % 15 % 7 %
Total long-lived assets by location	The following table presents total long-lived assets by location (in thousands): December 31, 2017 2016 United States $ 95,570 $ 35,791 Ireland 64,343 62,453 Italy 8,220 7,000 Other 1,947 2,246 Total long-lived assets (1) $ 170,080 $ 107,490 _________________________ (1) Long-lived assets consist of property and equipment.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of weighted-average assumptions used in Black-Scholes option pricing model and resulting weighted-average grant date fair value of share options granted	The table below shows, for all share option grants, the weighted-average assumptions used in the Black-Scholes option pricing model and the resulting weighted-average grant date fair value of share options granted in each of the past three years: Year Ended December 31, 2017 2016 2015 Grant date fair value $ 42.72 $ 40.45 $ 57.19 Volatility 35 % 39 % 39 % Expected term (years) 4.3 4.2 4.2 Range of risk-free rates 1.6-2.1% 0.8-1.6% 1.1-1.5% Expected dividend yield — % — % — %
Schedule of share-based compensation expense related to share options, RSUs, and grants under ESPP	Share-based compensation expense related to share options, RSUs and grants under our ESPP was as follows (in thousands): Year Ended December 31, 2017 2016 2015 Selling, general and administrative $ 83,218 $ 79,037 $ 74,653 Research and development 17,870 15,296 13,356 Cost of product sales 5,812 4,438 3,541 Total share-based compensation expense, pre-tax 106,900 98,771 91,550 Income tax benefit from share-based compensation expense (1) (21,792 ) (30,022 ) (20,071 ) Total share-based compensation expense, net of tax $ 85,108 $ 68,749 $ 71,479 __________________________ (1) Following adoption of ASU No. 2016-09 “Improvements to Employee Share-Based Payment Accounting” in 2016, the 2017 and 2016 income tax benefit includes excess tax benefits recognized.
Schedule of information and activity related to share option plans activity	The following table summarizes information as of December 31, 2017 and activity during 2017 related to our share option plans: Shares Subject to Outstanding Options (In thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (In thousands) Outstanding at January 1, 2017 4,513 $ 111.52 Options granted 1,402 137.46 Options exercised (428 ) 53.03 Options forfeited (241 ) 140.04 Options expired (101 ) 165.49 Outstanding at December 31, 2017 5,145 121.06 6.8 $ 124,032 Vested and expected to vest at December 31, 2017 4,896 120.27 6.7 123,206 Exercisable at December 31, 2017 2,976 108.45 5.6 116,822
Schedule of information and activity related to RSUs activity	The following table summarizes information as of December 31, 2017 and activity during 2017 related to our RSUs: Number of RSUs (in thousands) Weighted- Weighted- Aggregate Outstanding at January 1, 2017 997 $ 137.50 RSUs granted 561 137.46 RSUs released (385 ) 128.19 RSUs forfeited (110 ) 141.18 Outstanding at December 31, 2017 1,063 140.46 1.3 $ 143,113

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Schedule of restructuring amounts	The following table summarizes the amounts related to restructuring through December 31, 2017 (in thousands): Termination Benefits Facility Closure Costs Total Balance at December 31, 2014 $ 1,823 $ 118 $ 1,941 Expense 1,469 172 1,641 Payments (2,187 ) (290 ) (2,477 ) Balance at December 31, 2015 1,105 — 1,105 Expense 1,516 — 1,516 Payments (2,590 ) — (2,590 ) Balance at December 31, 2016 31 — 31 Expense 14 — 14 Payments (45 ) — (45 ) Balance at December 31, 2017 $ — $ — $ —

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Components of income from continuing operations before income tax provision (benefit)	The components of income before the income tax provision (benefit) and equity in loss of investees were as follows (in thousands): Year Ended December 31, 2017 2016 2015 Ireland $ 77,476 $ 179,570 $ 233,785 United States 271,440 312,904 285,420 Other 92,201 39,972 (83,272 ) Total $ 441,117 $ 532,446 $ 435,933
Details of income tax provision (benefit)	The following table sets forth the details of the income tax provision (benefit) (in thousands): Year Ended December 31, 2017 2016 2015 Current Ireland $ 28,045 $ 26,420 $ 29,748 United States 135,608 140,061 116,301 Other 14,198 9,918 28,708 Total current tax expense 177,851 176,399 174,757 Deferred, exclusive of other components below Ireland (19,709 ) (7,776 ) (6,655 ) United States (27,559 ) (9,120 ) 332 Other (19,108 ) (13,720 ) (40,532 ) Total deferred, exclusive of other components (66,376 ) (30,616 ) (46,855 ) Deferred, change in tax rates United States (155,679 ) 109 294 Other (3,536 ) (10,656 ) (21,797 ) Total deferred, change in tax rates (159,215 ) (10,547 ) (21,503 ) Total deferred tax benefit (225,591 ) (41,163 ) (68,358 ) Total income tax provision (benefit) $ (47,740 ) $ 135,236 $ 106,399
Reconciliation of income taxes at the statutory income tax rate to effective income tax rate	The reconciliation between the statutory income tax rate applied to income before income tax provision (benefit) and equity in loss of investees and our effective income tax rate was as follows: Year Ended December 31, 2017 2016 2015 Statutory income tax rate 12.5 % 12.5 % 12.5 % Impact of U.S. Tax Act (33.7 )% — % — % Foreign income tax rate differential 20.3 % 16.7 % 19.1 % Financing costs (5.6 )% (2.9 )% (0.4 )% Change in unrecognized tax benefits 2.8 % 3.3 % 3.6 % Change in valuation allowance (2.8 )% (0.1 )% (0.6 )% Non-deductible compensation 2.6 % 1.8 % 1.9 % Research and other tax credits (2.6 )% (2.8 )% (3.8 )% Change in estimates (2.1 )% — % (1.0 )% Excess tax benefits from share-based compensation (1.5 )% (1.5 )% — % Deduction on subsidiary equity (0.7 )% (2.4 )% (2.7 )% Change in tax rate (0.4 )% (1.8 )% (4.5 )% Acquisition-related costs — % 2.1 % — % Other 0.4 % 0.5 % 0.3 % Effective income tax rate (10.8 )% 25.4 % 24.4 %
Schedule of net deferred tax assets/(liabilities)	Significant components of our net deferred tax assets/(liabilities) were as follows (in thousands): December 31, 2017 2016 Deferred tax assets: Net operating loss carryforwards $ 125,966 $ 202,758 Tax credit carryforwards 130,782 114,192 Intangible assets 23,536 15,965 Share-based compensation 23,128 27,522 Accruals 45,088 49,187 Other 92,968 56,739 Total deferred tax assets 441,468 466,363 Valuation allowance (52,144 ) (53,184 ) Net deferred tax assets 389,324 413,179 Deferred tax liabilities: Acquired intangible assets (655,347 ) (910,460 ) Other (82,890 ) (44,392 ) Total deferred tax liabilities (738,237 ) (954,852 ) Net deferred tax liabilities $ (348,913 ) $ (541,673 ) The following table presents the breakdown between deferred tax assets and liabilities (in thousands): Year Ended December 31, 2017 2016 Deferred tax assets $ 34,559 $ 15,060 Deferred tax liabilities (383,472 ) (556,733 ) Net deferred tax liabilities $ (348,913 ) $ (541,673 )
Reconciliation of unrecognized tax benefits	A reconciliation of our gross unrecognized tax benefits follows (in thousands): December 31, 2017 2016 2015 Balance at the beginning of the year $ 90,910 $ 66,385 $ 40,802 Increases related to current year tax positions 27,875 26,873 23,664 Increases related to prior year tax positions 1,620 1,191 2,833 Decreases related to prior year tax positions (1,075 ) (255 ) (646 ) Lapse of the applicable statute of limitations (13,168 ) (3,284 ) (268 ) Balance at the end of the year $ 106,162 $ 90,910 $ 66,385

Quarterly Financial Data (Una49

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of interim financial results of operations on a quarterly basis	The following interim financial information presents our 2017 and 2016 results of operations on a quarterly basis (in thousands, except per share amounts): 2017 March 31 June 30 September 30 December 31 Revenues $ 376,053 $ 394,386 $ 411,855 $ 436,399 Gross margin (1) 348,613 360,983 376,768 404,847 Net income 86,511 105,604 63,526 232,207 Net income per ordinary share, basic 1.44 1.76 1.06 3.87 Net income per ordinary share, diluted 1.41 1.72 1.03 3.79 2016 March 31 June 30 September 30 December 31 Revenues $ 336,010 $ 381,161 $ 374,181 $ 396,621 Gross margin (1) 310,477 355,130 347,310 358,958 Net income 75,812 114,502 89,828 116,689 Net income per ordinary share, basic 1.24 1.89 1.49 1.95 Net income per ordinary share, diluted 1.21 1.85 1.45 1.91 __________________________ (1) Gross margin is computed by subtracting cost of product sales (excluding amortization and impairment of intangible assets) from product sales, net.

Summary of Significant Accoun50

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2017USD ($)Customer	Dec. 31, 2016USD ($)Customer	Dec. 31, 2015USD ($)	Sep. 30, 2017	Aug. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Number of customer with significant accounts receivable | Customer	5	5
Intangible asset amortization	$ 152,065,000	$ 101,994,000	$ 98,162,000
Advertising expenses	36,600,000	29,500,000	27,900,000
Total future lease payments	46,351,000
Increase to retained earnings	917,956,000	528,907,000
Accounting Standards Update 2014-09 | Pro Forma
Summary Of Significant Accounting Policies [Line Items]
Reduction to deferred revenue	2,000,000
Increase to retained earnings	2,000,000
Buildings | Palo Alto and Dublin
Summary Of Significant Accounting Policies [Line Items]
Total future lease payments	$ 215,200,000
Convertible Debt | 2021 Notes
Summary Of Significant Accounting Policies [Line Items]
Interest rate (as a percent)					1.875%
Convertible Debt | 2024 Notes
Summary Of Significant Accounting Policies [Line Items]
Interest rate (as a percent)				1.50%
Acquired Developed Technologies
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	14 years 11 months
Intangible asset amortization	$ 149,100,000	$ 99,000,000	$ 93,000,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	2 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	18 years
Customer Concentration Risk | Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Percentage of total revenues (as a percent)	90.00%	90.00%
Customer Concentration Risk | Accounts Receivable | Express Scripts
Summary Of Significant Accounting Policies [Line Items]
Percentage of total revenues (as a percent)	71.00%	73.00%
Customer Concentration Risk | Accounts Receivable | McKesson
Summary Of Significant Accounting Policies [Line Items]
Percentage of total revenues (as a percent)	15.00%	13.00%
Foreign exchange forward contracts | Derivatives not designated as hedging instruments
Summary Of Significant Accounting Policies [Line Items]
Notional amount	$ 98,700,000
Net asset fair value	10,500,000
Interest rate contracts | Derivatives designated as hedging instruments
Summary Of Significant Accounting Policies [Line Items]
Notional amount	300,000,000
Net asset fair value	$ 1,700,000

Summary of Significant Accoun51

Summary of Significant Accounting Policies - Schedule of Property and Equipment Estimated Useful Lives (Details)	12 Months Ended
	Dec. 31, 2017
Buildings
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	40 years
Manufacturing equipment and machinery | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years
Manufacturing equipment and machinery | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	10 years
Computer software and equipment
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	3 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	5 years

Summary of Significant Accoun52

Summary of Significant Accounting Policies - Schedule of Net Income Per Ordinary Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Net income attributable to Jazz Pharmaceuticals plc	$ 232,207	$ 63,526	$ 105,604	$ 86,511	$ 116,689	$ 89,828	$ 114,502	$ 75,812	$ 487,848	$ 396,831	$ 329,535
Denominator:
Weighted-average ordinary shares used in calculating net income per ordinary share attributable to Jazz Pharmaceuticals plc - basic (in shares)									60,018	60,500	61,232
Dilutive effect of employee equity incentive and purchase plans (in shares)									1,299	1,370	1,804
Weighted-average ordinary shares used in calculating net income per ordinary share attributable to Jazz Pharmaceuticals plc - diluted (in shares)									61,317	61,870	63,036
Net income per ordinary share :
Basic (in dollars per share)	$ 3.87	$ 1.06	$ 1.76	$ 1.44	$ 1.95	$ 1.49	$ 1.89	$ 1.24	$ 8.13	$ 6.56	$ 5.38
Diluted (in dollars per share)	$ 3.79	$ 1.03	$ 1.72	$ 1.41	$ 1.91	$ 1.45	$ 1.85	$ 1.21	$ 7.96	$ 6.41	$ 5.23

Summary of Significant Accoun53

Summary of Significant Accounting Policies - Schedule of Computation of Diluted Net Income (Loss) Per Share Having Anti-Dilutive Effect (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Exchangeable Senior Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	3,805	2,878	2,878
Options to purchase ordinary shares and RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	3,319	3,010	1,609
Ordinary shares under ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	14	93	0

Business Combination, Asset A54

Business Combination, Asset Acquisitions, and Disposition - Celator Acquisition, Additional Information (Details) - USD ($)	Jul. 12, 2016	Jun. 18, 2015	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Acquisition-related costs			$ 700,000	$ 10,800,000	$ 2,200,000
Product sales, net						$ 1,601,399,000	$ 1,477,261,000	$ 1,316,819,000
Credit Agreement June 2015 Amendment | Borrowings under revolving credit facility
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity	$ 1,250,000,000
Proceeds from revolving credit facility	1,000,000,000
Credit Agreement June 2015 | Term Loan
Business Acquisition [Line Items]
Face amount	$ 750,000,000	$ 750,000,000
Credit Agreement June 2015 | Borrowings under revolving credit facility
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity		750,000,000
Proceeds from revolving credit facility		$ 160,000,000
Celator Pharmaceuticals, Inc.
Business Acquisition [Line Items]
Share price (in dollars per share)	$ 30.25
Number of shares tendered during offer period in accordance with merger agreement (in shares)	36,516,173
Percentage of acquiree shares tendered during offer period (as a percent)	81.00%
Offer condition, percentage of common shares tendered (more than 50%) (as a percent)	50.00%
Number of acquiree shares delivered via notices of guaranteed delivery in accordance with merger agreement (in shares)	2,016,237
Percentage of acquiree shares delivered via notices of guaranteed delivery in accordance with merger agreement (as a percent)	4.00%
Total acquisition consideration	$ 1,500,000,000
Acquisition-related costs							10,000,000
Intangible assets	1,811,250,000
Celator Pharmaceuticals, Inc. | Acquired IPR&D assets
Business Acquisition [Line Items]
Acquired IPR&D assets	$ 1,800,000,000
Vyxeos
Business Acquisition [Line Items]
Product sales, net						$ 33,790,000	$ 0	$ 0
Acquired developed technologies
Business Acquisition [Line Items]
Intangible assets, useful life						14 years 11 months
Acquired developed technologies | Vyxeos
Business Acquisition [Line Items]
Intangible assets, useful life						18 years

Business Combination, Asset A55

Business Combination, Asset Acquisitions, and Disposition - Summary of Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jul. 12, 2016
Business Acquisition [Line Items]
Goodwill	$ 947,537	$ 893,810
Celator Pharmaceuticals, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents			$ 26,137
Other receivables			386
Prepaid expenses and deposits			151
Property and equipment			767
Intangible assets			1,811,250
Goodwill			252,825
Other non-current assets			43
Accrued liabilities			(19,076)
Deferred tax liability, net, non-current			(542,901)
Other non-current liabilities			(1,002)
Total acquisition consideration - cash paid			$ 1,528,580

Business Combination, Asset A56

Business Combination, Asset Acquisitions, and Disposition - Summary of Pro Forma Financial Information (Details) - Celator Pharmaceuticals, Inc. - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Pro forma adjustment, transaction-related expense	$ 13,600
Pro forma adjustment, interest expense	13,700	$ 25,900
Revenues	1,488,118	1,326,246
Net income attributable to Jazz Pharmaceuticals plc	$ 386,342	$ 283,113
Net income attributable to Jazz Pharmaceuticals plc per ordinary share - basic (in dollars per share)	$ 6.39	$ 4.62
Net income attributable to Jazz Pharmaceuticals plc per ordinary share - diluted (in dollars per share)	$ 6.24	$ 4.49

Business Combination, Asset A57

Business Combination, Asset Acquisitions, and Disposition - Collaboration and Option Agreement (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2017USD ($)productprogram	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable upfront payment		$ 85,000	$ 23,750	$ 0
ImmunoGen, Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of programs under agreement | program	3
Non-refundable upfront payment	$ 75,000
Additional development funding (up to $100 million)	$ 100,000
Development funding term	7 years
Number of projects subject to right to co-commercialize | product	1
Number of projects subject to right to co-commercialize under certain limited circumstances | product	2

Business Combination, Asset A58

Business Combination, Asset Acquisitions, and Disposition - License and Option Agreement (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Research and development		$ 198,442	$ 162,297	$ 135,253
Pfenex
Business Acquisition [Line Items]
Research and development		$ 19,500	800
Licensing expenses			15,800
Acquired IPR&D expense			$ 15,000
Pfenex | Upfront Payment
Business Acquisition [Line Items]
Upfront and option payments	$ 35,300
Pfenex | Milestone Payment
Business Acquisition [Line Items]
Potential payments under agreement for certain, development, regulatory, and sales related milestones	$ 189,000

Business Combination, Asset A59

Business Combination, Asset Acquisitions, and Disposition - Acquisition of Alize Pharma II S.A.S. (Details) $ in Thousands, € in Millions	1 Months Ended		12 Months Ended
	Mar. 31, 2016USD ($)	Mar. 31, 2016EUR (€)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Business Acquisition [Line Items]
Acquired in-process research and development			$ 85,000	$ 23,750	$ 0
Alize Pharma II S.A.S | Upfront Payment
Business Acquisition [Line Items]
Acquired in-process research and development	$ 8,800
Alize Pharma II S.A.S | Milestone Payment
Business Acquisition [Line Items]
Potential payments under agreement for certain development, regulatory, and sales related milestones | €		€ 10

Business Combination, Asset A60

Business Combination, Asset Acquisitions, and Disposition - Disposition (Details) - Certain EUSA Products - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Mar. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration		$ 34
Selling, General and Administrative Expenses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on disposal	$ 0.2

Cash and Available-for-Sale S61

Cash and Available-for-Sale Securities - Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 601,035	$ 425,963
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	601,035	425,963
Cash and Cash Equivalents	386,035	365,963	$ 988,785	$ 684,042
Investments	215,000	60,000
Cash
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	225,235	215,963
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	225,235	215,963
Cash and Cash Equivalents	225,235	215,963
Investments	0	0
Time deposits
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	235,000	210,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	235,000	210,000
Cash and Cash Equivalents	20,000	150,000
Investments	215,000	$ 60,000
Money market funds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	140,800
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	140,800
Cash and Cash Equivalents	140,800
Investments	$ 0

Fair Value Measurement - Assets

Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Available-for-sale securities:
Available-for-sale securities	$ 601,035	$ 425,963
Time deposits
Available-for-sale securities:
Available-for-sale securities	235,000	210,000
Money market funds
Available-for-sale securities:
Available-for-sale securities	140,800
Fair Value, Measurements, Recurring [Member] | Total Estimated Fair Value
Available-for-sale securities:
Totals	393,433	210,000
Liabilities:
Totals	5,409	0
Fair Value, Measurements, Recurring [Member] | Total Estimated Fair Value | Interest rate contracts
Available-for-sale securities:
Derivative asset	2,138	0
Liabilities:
Derivative Liability	392	0
Fair Value, Measurements, Recurring [Member] | Total Estimated Fair Value | Foreign exchange forward contracts
Available-for-sale securities:
Derivative asset	15,495	0
Liabilities:
Derivative Liability	5,017	0
Fair Value, Measurements, Recurring [Member] | Total Estimated Fair Value | Time deposits
Available-for-sale securities:
Available-for-sale securities	235,000	210,000
Fair Value, Measurements, Recurring [Member] | Total Estimated Fair Value | Money market funds
Available-for-sale securities:
Available-for-sale securities	140,800	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1)
Available-for-sale securities:
Totals	140,800
Liabilities:
Totals	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate contracts
Available-for-sale securities:
Derivative asset	0
Liabilities:
Derivative Liability	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign exchange forward contracts
Available-for-sale securities:
Derivative asset	0
Liabilities:
Derivative Liability	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Time deposits
Available-for-sale securities:
Available-for-sale securities	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Available-for-sale securities:
Available-for-sale securities	140,800
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2)
Available-for-sale securities:
Totals	252,633	210,000
Liabilities:
Totals	5,409	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Interest rate contracts
Available-for-sale securities:
Derivative asset	2,138	0
Liabilities:
Derivative Liability	392	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Foreign exchange forward contracts
Available-for-sale securities:
Derivative asset	15,495	0
Liabilities:
Derivative Liability	5,017	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Time deposits
Available-for-sale securities:
Available-for-sale securities	235,000	210,000
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Money market funds
Available-for-sale securities:
Available-for-sale securities	$ 0	$ 0

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Details) - Convertible Debt $ in Millions	Dec. 31, 2017USD ($)
2021 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of exchangeable senior notes	$ 577
2024 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of exchangeable senior notes	$ 543

Derivatives and Hedging Activ64

Derivatives and Hedging Activities - Additional Information (Details)	12 Months Ended
	Dec. 31, 2017USD ($)
Derivative [Line Items]
Losses recognized in AOCI to be reclassified over the next 12 months	$ 400,000
Gain on cash flow hedge ineffectiveness	100,000
Derivatives designated as hedging instruments | Interest rate contracts
Derivative [Line Items]
Notional amount	$ 300,000,000
Derivatives not designated as hedging instruments | Interest rate contracts
Derivative [Line Items]
Fixed interest rate	1.895%
Derivatives not designated as hedging instruments | Foreign exchange forward contracts
Derivative [Line Items]
Notional amount	$ 98,700,000
Contract term (up to 365 days)	365 days
Gain recognized in other income and expense	$ 10,500,000

Derivatives and Hedging Activ65

Derivatives and Hedging Activities - Gains on Derivative Instruments (Details) - Interest rate contracts - Cash Flow Hedges - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in accumulated other comprehensive loss, net of tax	$ (213)	$ 0
Loss reclassified from accumulated other comprehensive loss to interest expense, net of tax	$ 1,695	$ 0

Derivatives and Hedging Activ66

Derivatives and Hedging Activities - Fair Value of Outstanding Derivatives (Details) $ in Thousands	Dec. 31, 2017USD ($)
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 17,633
Liability Derivatives	5,409
Derivatives designated as hedging instruments | Interest rate contracts | Other non-current assets
Derivatives, Fair Value [Line Items]
Asset Derivatives	2,138
Derivatives designated as hedging instruments | Interest rate contracts | Accrued liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	392
Derivatives not designated as hedging instruments | Foreign exchange forward contracts | Accrued liabilities
Derivatives, Fair Value [Line Items]
Liability Derivatives	5,017
Derivatives not designated as hedging instruments | Foreign exchange forward contracts | Other current assets
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 15,495

Derivatives and Hedging Activ67

Derivatives and Hedging Activities - Offsetting Assets and Liabilities (Details) - Pro Forma $ in Thousands	Dec. 31, 2017USD ($)
Derivative assets
Gross Amounts of Recognized Assets/Liabilities	$ 1,639
Gross Amounts Offset in the Consolidated Balance Sheet	0
Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheet	1,639
Gross Amounts Not Offset in the Consolidated Balance Sheet
Derivative Financial Instruments	(875)
Cash Collateral Received (Pledged)	0
Net Amount	764
Derivative liabilities
Gross Amounts of Recognized Assets/Liabilities	(875)
Gross Amounts Offset in the Consolidated Balance Sheet	0
Net Amounts of Assets/ Liabilities Presented in the Consolidated Balance Sheet	875
Gross Amounts Not Offset in the Consolidated Balance Sheet
Derivative Financial Instruments	875
Cash Collateral Received (Pledged)	0
Net Amount	$ 0

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Components of Inventories
Raw materials	$ 3,542	$ 1,547
Work in process	15,692	18,689
Finished goods	24,011	13,815
Total inventories	$ 43,245	$ 34,051

Property and Equipment - Schedu

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 211,283	$ 139,632
Less accumulated depreciation and amortization	(41,203)	(32,142)
Property and equipment, net	170,080	107,490
Depreciation and amortization expense	13,100	11,800	$ 9,900
Build-to-suit facility
Property, Plant and Equipment [Line Items]
Property and equipment, gross	51,721	0
Land and buildings
Property, Plant and Equipment [Line Items]
Property and equipment, gross	46,729	46,033
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	28,779	9,328
Manufacturing equipment and machinery
Property, Plant and Equipment [Line Items]
Property and equipment, gross	23,586	19,596
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	21,738	33,427
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	19,969	17,832
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	12,814	10,980
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 5,947	$ 2,436

Goodwill and Intangible Asset70

Goodwill and Intangible Assets - Schedule of Gross Carrying Amount of Goodwill (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2016	$ 893,810
Foreign exchange	53,727
Balance at December 31, 2017	$ 947,537

Goodwill and Intangible Asset71

Goodwill and Intangible Assets - Schedule of Gross Carrying Amounts and Net Book Values of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived and Indefinite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,408,566	$ 1,491,768
Accumulated Amortization	(578,017)	(421,687)
Total	2,830,549	1,070,081
Intangible assets, gross	3,557,144	3,433,688
Intangible assets, net	2,979,127	3,012,001
Acquired IPR&D assets
Finite-Lived and Indefinite Lived Intangible Assets [Line Items]
Acquired IPR&D assets	$ 148,578	1,941,920
Acquired developed technologies
Finite-Lived and Indefinite Lived Intangible Assets [Line Items]
Remaining Weighted- Average Useful Life (In years)	14 years 11 months
Gross Carrying Amount	$ 3,392,832	1,477,618
Accumulated Amortization	(562,473)	(410,523)
Total	$ 2,830,359	1,067,095
Manufacturing contracts
Finite-Lived and Indefinite Lived Intangible Assets [Line Items]
Remaining Weighted- Average Useful Life (In years)	30 days
Gross Carrying Amount	$ 12,824	11,278
Accumulated Amortization	(12,634)	(8,292)
Total	$ 190	2,986
Trademarks
Finite-Lived and Indefinite Lived Intangible Assets [Line Items]
Remaining Weighted- Average Useful Life (In years)	0 years
Gross Carrying Amount	$ 2,910	2,872
Accumulated Amortization	(2,910)	(2,872)
Total	$ 0	$ 0

Goodwill and Intangible Asset72

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 31, 2017	Dec. 31, 2015	Dec. 31, 2017
Acquired Developed Technologies
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life			14 years 11 months
Vyxeos | Acquired Developed Technologies
Finite-Lived Intangible Assets [Line Items]
Increase in finite-lived intangible assets	$ 1,800
Intangible assets, useful life			18 years
Acquired IPR&D assets
Finite-Lived Intangible Assets [Line Items]
Impairment charge		$ 31.5
Acquired IPR&D assets | Vyxeos
Finite-Lived Intangible Assets [Line Items]
Decrease in indefinite-lived intangible assets	$ 1,800

Goodwill and Intangible Asset73

Goodwill and Intangible Assets - Schedule of Estimated Future Amortization Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 209,912
2,019	209,674
2,020	206,706
2,021	205,655
2,022	204,922
Thereafter	1,793,680
Total	$ 2,830,549	$ 1,070,081

Accrued Liabilities - Schedule

Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Rebates and other sales deductions	$ 81,368	$ 72,344
Employee compensation and benefits	54,930	43,363
Royalties	8,058	11,643
Accrued interest	7,297	5,179
Derivative instrument liabilities	5,409	0
Sales returns reserve	3,651	4,366
Professional fees	3,213	4,596
Selling and marketing accruals	3,189	3,924
Inventory-related accruals	3,002	3,350
Accrued construction-in-progress	2,827	1,597
Clinical trial accruals	2,181	10,139
Accrued contract termination fees	0	11,612
Other	23,654	21,155
Total accrued liabilities	$ 198,779	$ 193,268

Debt - Schedule of Debt (Detail

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Principal amount	$ 1,826,758
Total debt	1,581,038	$ 2,029,625
Less current portion	40,605	36,094
Total long-term debt	1,540,433	1,993,531
Borrowings under revolving credit facility
Debt Instrument [Line Items]
Total debt	0	850,000
Convertible Debt | 2021 Notes
Debt Instrument [Line Items]
Principal amount	575,000	575,000
Unamortized discount and debt issuance costs	(81,627)	(101,094)
Total debt	493,373	473,906
Convertible Debt | 2024 Notes
Debt Instrument [Line Items]
Principal amount	575,000	0
Unamortized discount and debt issuance costs	(158,680)	0
Total debt	416,320	0
Term loan
Debt Instrument [Line Items]
Total debt	$ 671,345	$ 705,719

Debt - Credit Agreement (Detail

Debt - Credit Agreement (Details) - USD ($)	Jul. 12, 2016	Jun. 18, 2015	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt outstanding				$ 1,826,758,000
Loss on extinguishment and modification of debt			$ 600,000	0	$ 638,000	$ 16,815,000
Borrowings under revolving credit facility | Credit Agreement June 2015
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity		$ 750,000,000
Proceeds from revolving credit facility		160,000,000
Borrowings under revolving credit facility | Credit Agreement June 2015 Amendment
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 1,250,000,000
Proceeds from revolving credit facility	$ 1,000,000,000
Long-term debt outstanding				0
Undrawn revolving credit facilities				1,250,000,000
Borrowings under revolving credit facility | Credit Agreement June 2015 Amendment | Minimum
Debt Instrument [Line Items]
Commitment fee percentage (as a percent)	0.25%
Borrowings under revolving credit facility | Credit Agreement June 2015 Amendment | Maximum
Debt Instrument [Line Items]
Commitment fee percentage (as a percent)	0.35%
Term Loan | Credit Agreement June 2015
Debt Instrument [Line Items]
Face amount	$ 750,000,000	750,000,000
Loss on extinguishment and modification of debt					$ 600,000	16,800,000
Term Loan | Credit Agreement 2012
Debt Instrument [Line Items]
Extinguishment of debt		$ 893,100,000
Unamortized deferred financing costs and unamortized discount						16,000,000
Debt issuance cost						$ 800,000
Term Loan | Credit Agreement June 2015 Amendment
Debt Instrument [Line Items]
Long-term debt outstanding	$ 721,900,000			$ 676,800,000
Interest rate during the period				3.32%
Effective interest rate (as a percent)				2.97%
Principal repayment in year one and two (as a percent)	5.00%
Principal repayment in year three (as a percent)	7.50%
Principal repayment in year four (as a percent)	10.00%
Principal repayment in year five (as a percent)	12.50%
Term Loan | Credit Agreement June 2015 Amendment | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Term Loan | Credit Agreement June 2015 Amendment | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.25%
Term Loan | Credit Agreement June 2015 Amendment | Prime Rate | Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.50%
Term Loan | Credit Agreement June 2015 Amendment | Prime Rate | Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.25%

Debt - Exchangeable Senior Note

Debt - Exchangeable Senior Notes (Details)	1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 31, 2014USD ($)d$ / shares	Sep. 30, 2017USD ($)d$ / shares	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Debt Instrument [Line Items]
Repayments under revolving credit facility			$ 850,000,000	$ 150,000,000	$ 160,000,000
Interest expense, net			$ 37,800,000	$ 27,500,000	$ 26,500,000
Convertible Debt
Debt Instrument [Line Items]
Ownership percentage (as a percent)			100.00%
2024 Notes | Convertible Debt
Debt Instrument [Line Items]
Face amount		$ 575,000,000
Interest rate (as a percent)		1.50%
Percentage of conversion price		130.00%
Number of trading days | d		20
Number of consecutive days in trading period | d		30
Conversion rate of shares		4.5659
Conversion denominator		$ 1,000
Debt conversion price (in dollars per share) | $ / shares		$ 219.02
Effective interest rate (as a percent)			6.80%
Debt term		7 years
Debt issuance cost		$ 15,600,000
Carrying value of the equity component			$ 149,800,000
2021 Notes | Convertible Debt
Debt Instrument [Line Items]
Interest rate (as a percent)	1.875%
Percentage of conversion price	130.00%
Number of trading days | d	20
Number of consecutive days in trading period | d	30
Conversion rate of shares	5.0057
Conversion denominator	$ 1,000
Debt conversion price (in dollars per share) | $ / shares	$ 199.77
Effective interest rate (as a percent)			6.40%
Debt term	7 years
Debt issuance cost	$ 16,100,000
Carrying value of the equity component			$ 126,900,000
Borrowings under revolving credit facility
Debt Instrument [Line Items]
Repayments under revolving credit facility		$ 500,000,000

Debt - Schedule of Debt Maturit

Debt - Schedule of Debt Maturities (Details) $ in Thousands	Dec. 31, 2017USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2,018	$ 40,605
2,019	58,652
2,020	76,700
2,021	1,075,801
Thereafter	575,000
Total debt	$ 1,826,758

Deferred Revenue - Narrative (D

Deferred Revenue - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)agreement	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2006USD ($)payment
License Development and Commercialization Agreements
Other Long Term Liabilities [Line Items]
Number of license, development, and commercialization agreements | agreement	2
Contract revenues	$ 5.6
Recognition period	4 years
UCB Pharma Limited
Other Long Term Liabilities [Line Items]
Contract revenues	$ 1.1	$ 1.1	$ 1.1
Number of payments received upfront from UCB | payment				2
Deferred contract revenues upfront payment received				$ 15

Commitments and Contingencies -

Commitments and Contingencies - Leases and Other Commitments (Details) $ in Thousands	1 Months Ended			12 Months Ended
	Sep. 30, 2017renewal_term	Aug. 31, 2016USD ($)	Jan. 31, 2015renewal_term	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Other Commitments [Line Items]
Lease expense				$ 14,982	$ 11,600	$ 10,479
Other non-current liabilities				176,608	112,617
Total future lease payments				46,351
Noncancelable purchase commitments due within one year				46,300
Buildings | Palo Alto
Other Commitments [Line Items]
Operating lease, term	12 years		12 years
Financing obligation				62,900
Lease expense				2,400	$ 1,900	$ 1,800
Buildings | Palo Alto | Property, Plant and Equipment
Other Commitments [Line Items]
Construction-in-progress				17,400
Buildings | Palo Alto | Other Non-current Liabilities
Other Commitments [Line Items]
Other non-current liabilities				$ 17,400
Buildings | Palo Alto | Lease Agreements
Other Commitments [Line Items]
Number of renewal option terms | renewal_term	2		2
Operating lease, extended term option	5 years		5 years
Buildings | Dublin
Other Commitments [Line Items]
Operating lease, term		20 years
Early termination, lease term option 1		8 years
Notice of termination period		1 year
Early termination, lease term option 2		15 years
Total future lease payments		$ 19,800

Commitments and Contingencies81

Commitments and Contingencies - Schedule Of Future Minimum Lease Payments Under Noncancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2017USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,018	$ 9,102
2,019	8,166
2,020	6,111
2,021	5,212
2,022	5,007
Thereafter	12,753
Total	46,351
Facility
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,018	6,297
2,019	9,142
2,020	14,392
2,021	14,824
2,022	15,269
Thereafter	135,473
Total	$ 195,397

Commitments and Contingencies82

Commitments and Contingencies - Legal Proceedings and Other Contingencies Narrative (Details)	Apr. 05, 2017	Jun. 29, 2016lawsuit	Mar. 31, 2017claim_under_petition	Jul. 31, 2016patent	Mar. 31, 2016claim_under_petition	Apr. 30, 2015litigation_case	Jan. 31, 2015patent	Dec. 31, 2017lawsuit
Xyrem
Loss Contingencies [Line Items]
Exclusivity grace period	6 months
Initial Term	5 years
Sales period extension that results in a royal rate increase	1 year
Number of claims settled | lawsuit								3
Celator Acquisition | Celator Pharmaceuticals, Inc.
Loss Contingencies [Line Items]
Number of claims filed during the period | lawsuit		2
Pending Litigation | Xyrem
Loss Contingencies [Line Items]
Number of patents named in review petitions | patent							6
Number of ANDAs filed by third parties | patent							7
Number of patents deemed unenforceable | patent				6
Number petition claims under patent review awaiting decision					3
Number of petition claims denied under patent					25
Number of petition claims under patent review					28
Number of petition claims deemed unpatentable			3
Pending Litigation | Xyrem ANDA Matters
Loss Contingencies [Line Items]
Number of litigation cases after consolidation | litigation_case						1

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - Ordinary Shares - USD ($) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2017	Nov. 30, 2016	Nov. 30, 2015	May 31, 2013
Stockholders' Equity Note [Line Items]
Stock repurchased	$ 98,800,000
Stock repurchased (in shares)	0.7
Treasury stock acquired, average cost per share (in dollars per share)	$ 140.34
May 2013 Share Repurchase Program
Stockholders' Equity Note [Line Items]
Total amount authorized for repurchase of shares under share repurchase program				$ 200,000,000
November 2015 Share Repurchase Program
Stockholders' Equity Note [Line Items]
Total amount authorized for repurchase of shares under share repurchase program			$ 300,000,000
Remaining amount authorized for repurchase of shares	$ 182,700,000
November 2016 Share Repurchase Program
Stockholders' Equity Note [Line Items]
Total amount authorized for repurchase of shares under share repurchase program		$ 300,000,000

Shareholders' Equity - Schedule

Shareholders' Equity - Schedule of Authorized But Unissued Ordinary Shares (Details) shares in Thousands	Dec. 31, 2017shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	17,041
2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	16,026
Amended and Restated 2007 Non-Employee Directors Stock Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	481
2007 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	339
Amended and Restated Directors Deferred Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	178
2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized but unissued ordinary shares reserved (in shares)	17

Comprehensive Income (Loss) - C

Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Loss (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 1,877,339
Other comprehensive income (loss) before reclassifications	174,760
Amounts reclassified from accumulated other comprehensive loss	1,695
Other comprehensive income, net	176,455
Ending balance	2,713,097
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	0
Other comprehensive income (loss) before reclassifications	(213)
Amounts reclassified from accumulated other comprehensive loss	1,695
Other comprehensive income, net	1,482
Ending balance	1,482
Foreign Currency Translation Adjustments
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(317,333)
Other comprehensive income (loss) before reclassifications	174,973
Amounts reclassified from accumulated other comprehensive loss	0
Other comprehensive income, net	174,973
Ending balance	(142,360)
Total Accumulated Other Comprehensive Loss
Increase (Decrease) in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(317,333)
Ending balance	$ (140,878)

Segment and Other Information -

Segment and Other Information - Narrative (Details)	12 Months Ended
	Dec. 31, 2017Segment
Segment Reporting [Abstract]
Number of operating business segments	1

Segment and Other Information87

Segment and Other Information - Summary of Total Revenues (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Product sales, net									$ 1,601,399	$ 1,477,261	$ 1,316,819
Royalties and contract revenues									17,294	10,712	7,984
Total revenues	$ 436,399	$ 411,855	$ 394,386	$ 376,053	$ 396,621	$ 374,181	$ 381,161	$ 336,010	1,618,693	1,487,973	1,324,803
Xyrem
Segment Reporting Information [Line Items]
Product sales, net									1,186,699	1,107,616	955,187
Erwinaze/Erwinase
Segment Reporting Information [Line Items]
Product sales, net									197,340	200,678	203,261
Defitelio/defibrotide
Segment Reporting Information [Line Items]
Product sales, net									133,650	108,952	70,731
Vyxeos
Segment Reporting Information [Line Items]
Product sales, net									33,790	0	0
Prialt® (ziconotide) intrathecal infusion
Segment Reporting Information [Line Items]
Product sales, net									27,361	29,120	26,440
Other
Segment Reporting Information [Line Items]
Product sales, net									$ 22,559	$ 30,895	$ 61,200

Segment and Other Information88

Segment and Other Information - Summary of Total Revenues Attributed to Geographic Sources (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 436,399	$ 411,855	$ 394,386	$ 376,053	$ 396,621	$ 374,181	$ 381,161	$ 336,010	$ 1,618,693	$ 1,487,973	$ 1,324,803
United States
Segment Reporting Information [Line Items]
Total revenues									1,463,457	1,354,921	1,192,879
Europe
Segment Reporting Information [Line Items]
Total revenues									122,789	106,146	103,614
All other
Segment Reporting Information [Line Items]
Total revenues									$ 32,447	$ 26,906	$ 28,310

Segment and Other Information89

Segment and Other Information - Summary of Revenues from Customers Representing More Than 10% of Total Revenues (Details) - Customer Concentration Risk - Revenues	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Express Scripts
Concentration Risk [Line Items]
Percentage of total revenues (as a percent)	73.00%	74.00%	72.00%
McKesson
Concentration Risk [Line Items]
Percentage of total revenues (as a percent)	16.00%	15.00%	7.00%

Segment and Other Information90

Segment and Other Information - Total Long-Lived Assets by Location (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 170,080	$ 107,490
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	95,570	35,791
Ireland
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	64,343	62,453
Italy
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	8,220	7,000
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,947	$ 2,246

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details)	Jan. 01, 2018shares	Jan. 18, 2012shares	Oct. 24, 2011	Dec. 31, 2011periodshares	Aug. 31, 2010shares	Sep. 30, 2011	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Jan. 17, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized tax benefits related to share options exercised | $							$ 8,900,000	$ 8,300,000	$ 400,000
Aggregate intrinsic value of share options exercised | $							38,900,000	36,100,000	93,300,000
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested stock options | $							$ 73,400,000
Unrecognized compensation cost, weighted-average period of recognition (in years)							2 years 6 months 20 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)							4 years
Unrecognized compensation cost related to unvested RSUs | $							$ 88,600,000
Unrecognized compensation cost, weighted-average period of recognition (in years)							2 years 5 months
RSUs weighted-average grant date fair value (in dollars per share) | $ / shares							$ 137.46
Number of RSUs released (in shares)							385,000
Shares issued (in shares)							250,000
Shares withheld for tax purposes (in shares)							135,000
Total fair value of shares vested | $							$ 53,200,000	59,200,000	72,200,000
2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service periods (in years)				4 years
Shares authorized for issuance (in shares)							21,729,232
2011 Equity Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants expiration period (in years)				10 years
2011 Equity Incentive Plan, Option One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance, annual automatic increase, maximum percentage of outstanding shares				4.50%
2011 Equity Incentive Plan, Option Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved under plan (in shares)				5,000,000
2007 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance (in shares)		1,000,000
2007 Equity Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service periods (in years)		1 year								3 years
2007 Equity Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service periods (in years)		3 years								5 years
Grants expiration period (in years)		10 years								10 years
2007 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance (in shares)							2,660,000
ESPP discount rate (as a percent)				15.00%
ESPP offering period (in months)				24 months
Number of purchase periods within each ESPP offering period | period				4
Number of shares available for issuance (in shares)				175,000
Unrecognized compensation cost related to grants under the ESPP | $							$ 2,800,000
2007 Employee Stock Purchase Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, weighted-average period of recognition (in years)							1 year
2007 Employee Stock Purchase Plan Option One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance, annual automatic increase, maximum percentage of outstanding shares				1.50%
2007 Employee Stock Purchase Plan Option Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved under plan (in shares)				1,000,000
2007 Directors Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance under deferred compensation plan (in shares)							903,938
2007 Directors Option Plan | Initial Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)						3 years
2007 Directors Option Plan | Annual Automatic Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)						1 year
2007 Directors Option Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service periods (in years)			1 year
2007 Directors Option Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service periods (in years)			3 years
Grants expiration period (in years)			10 years
Directors Deferred Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved under plan (in shares)					200,000
Recorded expense related to retainer fees earned and deferred | $							$ 0	$ 0	$ 0
Deferred compensation arrangement with individuals, shares unissued (in shares)							14,499
Subsequent Event | 2011 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved under plan (in shares)	2,695,413
Subsequent Event | 2007 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved under plan (in shares)	898,471

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Weighted-Average Assumptions Used in Black-Scholes Option Pricing Model and Resulting Weighted-Average Grant Date Fair Value of Share Options Granted (Details) - Share Options - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value (in dollars per share)	$ 42.72	$ 40.45	$ 57.19
Volatility (as a percent)	35.00%	39.00%	39.00%
Expected term (in years)	4 years 3 months	4 years 2 months	4 years 2 months
Range of risk-free rates, minimum (as a percent)	1.60%	0.80%	1.10%
Range of risk-free rates, maximum (as a percent)	2.10%	1.60%	1.50%
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%

Share-Based Compensation - Sc93

Share-Based Compensation - Schedule of Stock-Based Compensation Expense Related to Stock Options, RSUs, Ordinary Shares Credited to Directors' Phantom Share Accounts and Grants under ESPP (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense, pre-tax	$ 106,900	$ 98,771	$ 91,550
Income tax benefit from share-based compensation expense	(21,792)	(30,022)	(20,071)
Total share-based compensation expense, net of tax	85,108	68,749	71,479
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense, pre-tax	83,218	79,037	74,653
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense, pre-tax	17,870	15,296	13,356
Cost of product sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation expense, pre-tax	$ 5,812	$ 4,438	$ 3,541

Share-Based Compensation - Sc94

Share-Based Compensation - Schedule of Share Option Plans Activity (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Shares Subject to Outstanding Options [Roll Forward]
Outstanding, beginning balance (in shares) | shares	4,513
Options granted (in shares) | shares	1,402
Options exercised (in shares) | shares	(428)
Options forfeited (in shares) | shares	(241)
Options expired (in shares) | shares	(101)
Outstanding, ending balance (in shares) | shares	5,145
Vested and expected to vest (in shares) | shares	4,896
Exercisable, balance (in shares) | shares	2,976
Weighted Average Exercise Price (in dollars per share) [Roll Forward]
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 111.52
Options granted (in dollars per share) | $ / shares	137.46
Options exercised (in dollars per share) | $ / shares	53.03
Options forfeited (in dollars per share) | $ / shares	140.04
Options expired (in dollars per share) | $ / shares	165.49
Outstanding, ending balance (in dollars per share) | $ / shares	121.06
Vested and expected to vest (in dollars per share) | $ / shares	120.27
Exercisable (in dollars per share) | $ / shares	$ 108.45
Weighted- Average Remaining Contractual Term (Years)
Weighted-average remaining contractual term, outstanding	6 years 9 months 2 days
Weighted-average remaining contractual term, vested and expected to vest, exercisable	6 years 8 months 20 days
Weighted-average remaining contractual term, exercisable	5 years 7 months 6 days
Aggregate Intrinsic Value
Aggregate intrinsic value, outstanding | $	$ 124,032
Aggregate intrinsic value, vested and expected to vest | $	123,206
Aggregate intrinsic value, exercisable | $	$ 116,822

Share-Based Compensation - Sc95

Share-Based Compensation - Schedule of RSUs Activity (Details) - Restricted Stock Units (RSUs) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Number of RSUs [Roll Forward]
Number of RSUs, outstanding, beginning balance (in shares) | shares	997
Number of RSUs granted (in shares) | shares	561
Number of RSUs released (in shares) | shares	(385)
Number of RSUs forfeited (in shares) | shares	(110)
Number of RSUs, outstanding, ending balance (in shares) | shares	1,063
Weighted-Average Grant-Date Fair Value [Roll Forward]
Weighted-average grant-date fair value, outstanding, beginning balance (in dollars per share) | $ / shares	$ 137.50
Weighted-average grant-date fair value, RSUs granted (in dollars per share) | $ / shares	137.46
Weighted-average grant-date fair value, RSUs released (in dollars per share) | $ / shares	128.19
Weighted-average grant-date fair value, RSUs forfeited (in dollars per share) | $ / shares	141.18
Weighted-average grant-date fair value, outstanding, ending balance (in dollars per share) | $ / shares	$ 140.46
Weighted-average remaining contractual term, outstanding	1 year 4 months
Aggregate intrinsic value, outstanding | $	$ 143,113

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Contribution Plan Disclosure [Line Items]
Expenses related to defined contribution plans	$ 5.5	$ 3.4	$ 2.2
Ireland
Defined Contribution Plan Disclosure [Line Items]
Expenses related to defined contribution plans	$ 1	0.8	0.6
Defined contribution plans, employer matching percentage of employee's eligible contributions (as a percent)	8.00%
United States
Defined Contribution Plan Disclosure [Line Items]
Expenses related to defined contribution plans	$ 3.7	1.9	1.1
United Kingdom
Defined Contribution Plan Disclosure [Line Items]
Expenses related to defined contribution plans	$ 0.7	0.6	$ 0.4
Defined contribution plans, employer matching percentage of employee's eligible contributions (as a percent)	12.00%
France
Defined Contribution Plan Disclosure [Line Items]
Accrued retirement liability	$ 0.3	0.3
Italy
Defined Contribution Plan Disclosure [Line Items]
Accrued retirement liability	$ 0.3	$ 0.3

Restructuring - Additional Info

Restructuring - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Termination benefit costs incurred			$ 3
One-time Termination Benefits | France, Italy, and the United Kingdom
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1.5	$ 1.5
Facility Closure Costs | Selling, General and Administrative Expenses
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 0.2

Restructuring - Schedule of Res

Restructuring - Schedule of Restructuring (Details) - Accrued liabilities - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 31	$ 1,105	$ 1,941
Expense	14	1,516	1,641
Payments	(45)	(2,590)	(2,477)
Restructuring reserve, ending balance	0	31	1,105
Termination Benefits
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	31	1,105	1,823
Expense	14	1,516	1,469
Payments	(45)	(2,590)	(2,187)
Restructuring reserve, ending balance	0	31	1,105
Facility Closure Costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0	0	118
Expense	0	0	172
Payments	0	0	(290)
Restructuring reserve, ending balance	$ 0	$ 0	$ 0

Income Taxes - Components of In

Income Taxes - Components of Income Before Income Tax Provision (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of Income from Continuing Operations before Income Tax Provision (Benefit)
Ireland	$ 77,476	$ 179,570	$ 233,785
United States	271,440	312,904	285,420
Other	92,201	39,972	(83,272)
Income before income tax provision (benefit) and equity in loss of investees	$ 441,117	$ 532,446	$ 435,933

Income Taxes - Details of Incom

Income Taxes - Details of Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
Ireland	$ 28,045	$ 26,420	$ 29,748
United States	135,608	140,061	116,301
Other	14,198	9,918	28,708
Total current tax expense	177,851	176,399	174,757
Deferred
Ireland	(19,709)	(7,776)	(6,655)
United States	(27,559)	(9,120)	332
Other	(19,108)	(13,720)	(40,532)
Total deferred, exclusive of other components	(66,376)	(30,616)	(46,855)
Deferred, change in tax rates
United States	(155,679)	109	294
Other	(3,536)	(10,656)	(21,797)
Total deferred, change in tax rates	(159,215)	(10,547)	(21,503)
Total deferred tax benefit	(225,591)	(41,163)	(68,358)
Total income tax provision (benefit)	$ (47,740)	$ 135,236	$ 106,399

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Tax Cuts and Jobs Act of 2017 - Provisional income tax benefit		$ 155,100
Tax Cuts and Jobs Act of 2017 - Provisional transition tax expense		6,300
Tax Cuts and Jobs Act of 2017 - Provisional deferred tax asset related to deductibility of certain executive compensation	$ 7,500	7,500
Income tax provision (benefit)		(47,740)	$ 135,236	$ 106,399
Tax Cuts and Jobs Act of 2017 - Net benefit of the impacts	148,800	$ 148,800
Effective income tax rate (as a percent)		(10.80%)	25.40%	24.40%
Tax Cuts and Jobs Act of 2017 - Effective income tax rate excluding impact of the U.S. Tax Act (as a percent)		22.90%
Operating Loss Carryforwards [Line Items]
Statutory income tax rate (as a percent)		12.50%	12.50%	12.50%
Increase (decrease) in valuation allowance		$ (1,000)	$ 19,200	$ 4,300
Deferred tax assets, valuation allowance	52,144	52,144	53,184
Cumulated unremitted earnings of overseas subsidiaries	1,700,000	1,700,000	1,200,000
Unrecognized tax benefits that would impact the effective tax rate	73,500	$ 73,500	$ 61,000
Ireland
Operating Loss Carryforwards [Line Items]
Statutory income tax rate (as a percent)		12.50%	12.50%	12.50%
U.S. Federal
Operating Loss Carryforwards [Line Items]
NOL carryforwards	388,800	$ 388,800
Tax credit carryforwards	117,600	117,600
U.S. Federal | 2018
Operating Loss Carryforwards [Line Items]
Annual limitation on utilization of certain acquired federal NOLs	410,600	410,600
U.S. Federal | 2019
Operating Loss Carryforwards [Line Items]
Annual limitation on utilization of certain acquired federal NOLs	30,700	30,700
U.S. Federal | 2020 to 2032
Operating Loss Carryforwards [Line Items]
Annual limitation on utilization of certain acquired federal NOLs	311,000	311,000
U.S. Federal | EUSA Pharma Acquisition
Operating Loss Carryforwards [Line Items]
NOL carryforwards					$ 93,400
U.S. Federal | Celator Pharmaceuticals, Inc.
Operating Loss Carryforwards [Line Items]
NOL carryforwards			$ 213,600
U.S. State
Operating Loss Carryforwards [Line Items]
NOL carryforwards	124,400	124,400
Tax credit carryforwards	10,500	10,500
Foreign Tax Authorities
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	4,600	4,600
Foreign Tax Authorities | United Kingdom
Operating Loss Carryforwards [Line Items]
NOL carryforwards	59,000	59,000
Foreign Tax Authorities | Luxembourg
Operating Loss Carryforwards [Line Items]
NOL carryforwards	$ 84,000	84,000
French Tax Authorities
Operating Loss Carryforwards [Line Items]
Proposed additional tax including interest and penalties		45,900
Tax Cuts And Jobs Act Of 2017, Foreign Tax Credits
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowance		5,900
Valuation Allowance, Operating Loss Carryforwards
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowance		(6,600)	$ 17,900	$ (2,400)
Utilization Of NOL Carryforwards Which Previously Carried Valuation Allowance
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowance		$ (9,100)

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation [Abstract]
Statutory income tax rate	12.50%	12.50%	12.50%
Impact of U.S. Tax Act	(33.70%)	0.00%	0.00%
Foreign income tax rate differential	20.30%	16.70%	19.10%
Financing costs	(5.60%)	(2.90%)	(0.40%)
Change in unrecognized tax benefits	2.80%	3.30%	3.60%
Change in valuation allowance	(2.80%)	(0.10%)	(0.60%)
Non-deductible compensation	2.60%	1.80%	1.90%
Research and other tax credits	(2.60%)	(2.80%)	(3.80%)
Change in estimates	(2.10%)	0.00%	(1.00%)
Excess tax benefits from share-based compensation	(1.50%)	(1.50%)	0.00%
Deduction on subsidiary equity	(0.70%)	(2.40%)	(2.70%)
Change in tax rate	(0.40%)	(1.80%)	(4.50%)
Acquisition-related costs	0.00%	2.10%	0.00%
Other	0.40%	0.50%	0.30%
Effective income tax rate	(10.80%)	25.40%	24.40%

Income Taxes - Schedule of Net

Income Taxes - Schedule of Net Deferred Tax Assets/(Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Net operating loss carryforwards	$ 125,966	$ 202,758
Tax credit carryforwards	130,782	114,192
Intangible assets	23,536	15,965
Share-based compensation	23,128	27,522
Accruals	45,088	49,187
Other	92,968	56,739
Total deferred tax assets	441,468	466,363
Valuation allowance	(52,144)	(53,184)
Net deferred tax assets	389,324	413,179
Deferred tax liabilities:
Acquired intangible assets	(655,347)	(910,460)
Other	(82,890)	(44,392)
Total deferred tax liabilities	(738,237)	(954,852)
Net deferred tax liabilities	$ (348,913)	$ (541,673)

Income Taxes - Current and Non-

Income Taxes - Current and Non-current Deferred Assets/(Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred tax assets	$ 34,559	$ 15,060
Deferred tax liabilities	(383,472)	(556,733)
Net deferred tax liabilities	$ (348,913)	$ (541,673)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Beginning and Ending Amounts of Unrecognized Tax Benefits
Balance at the beginning of the year	$ 90,910	$ 66,385	$ 40,802
Increases related to current year tax positions	27,875	26,873	23,664
Increases related to prior year tax positions	1,620	1,191	2,833
Decreases related to prior year tax positions	(1,075)	(255)	(646)
Lapse of the applicable statute of limitations	(13,168)	(3,284)	(268)
Balance at the end of the year	$ 106,162	$ 90,910	$ 66,385

Quarterly Financial Data (Un106

Quarterly Financial Data (Unaudited) - Schedule Of Interim Financial Information Presents Results Of Operations On Quarterly Basis (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Data [Line Items]
Revenues	$ 436,399	$ 411,855	$ 394,386	$ 376,053	$ 396,621	$ 374,181	$ 381,161	$ 336,010	$ 1,618,693	$ 1,487,973	$ 1,324,803
Gross margin	404,847	376,768	360,983	348,613	358,958	347,310	355,130	310,477
Net income	$ 232,207	$ 63,526	$ 105,604	$ 86,511	$ 116,689	$ 89,828	$ 114,502	$ 75,812	$ 487,848	$ 396,831	$ 329,535
Net income per ordinary share, basic (in dollars per share)	$ 3.87	$ 1.06	$ 1.76	$ 1.44	$ 1.95	$ 1.49	$ 1.89	$ 1.24	$ 8.13	$ 6.56	$ 5.38
Net income per ordinary share, diluted (in dollars per share)	$ 3.79	$ 1.03	$ 1.72	$ 1.41	$ 1.91	$ 1.45	$ 1.85	$ 1.21	$ 7.96	$ 6.41	$ 5.23
Research and development									$ 198,442	$ 162,297	$ 135,253
Legal proceedings and restructuring expense				$ 6,000				$ 6,100
Transaction and integration related costs					$ 700	$ 10,800	$ 2,200
Loss on extinguishment and modification of debt						600			0	$ 638	$ 16,815
One-time contract termination charge					$ 11,600
Tax Cuts and Jobs Act of 2017 - Net benefit of the impacts	$ 148,800								$ 148,800
Upfront and Milestone Payments
Quarterly Financial Data [Line Items]
Research and development	$ 26,500	$ 75,000				$ 15,000		$ 8,800

Schedule II Valuation and Qu107

Schedule II Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 287	$ 489	$ 530
Additions charged to costs and expenses	231	168	0
Other Additions	0	0	0
Deductions	(122)	(370)	(41)
Balance at end of period	396	287	489
Allowance for sales discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	118	181	238
Additions charged to costs and expenses	1,087	1,334	2,900
Other Additions	0	0	0
Deductions	(1,102)	(1,397)	(2,957)
Balance at end of period	103	118	181
Allowance for chargebacks
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	4,749	3,023	2,715
Additions charged to costs and expenses	41,941	41,991	39,079
Other Additions	0	0	0
Deductions	(43,027)	(40,265)	(38,771)
Balance at end of period	3,663	4,749	3,023
Deferred tax asset valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	53,184	33,949	29,697
Additions charged to costs and expenses	7,509	19,328	5,044
Other Additions	5,581	5,544	1,888
Deductions	(14,130)	(5,637)	(2,680)
Balance at end of period	$ 52,144	$ 53,184	$ 33,949