Basis of Presentation and Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Use of Estimates The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of the SEC Regulation S-X. Accordingly, they should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2017 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017, filed with the SEC on February 22, 2018 (the Form 10-K). The accompanying unaudited condensed consolidated financial statements include the accounts of La Jolla Pharmaceutical Company and its wholly-owned subsidiaries. All significant inter-company transactions and balances have been eliminated in consolidation. The unaudited condensed consolidated financial statements contain all normal recurring accruals and adjustments that, in the opinion of management, are necessary to present fairly the condensed consolidated balance sheet of the Company at June 30, 2018, the condensed consolidated statement of operations for the three and six months ended June 30, 2018 and the condensed consolidated statement of cash flows for the six months ended June 30, 2018. The preparation of the Company’s unaudited condensed consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenue and expenses and the disclosure of contingent assets and liabilities in the Company’s unaudited condensed consolidated financial statements and the accompanying notes. Actual results could differ materially from those estimates. The results of operations for the three and six months ended June 30, 2018 are not necessarily indicative of the results to be expected for the full year or any future interim periods. The accompanying condensed consolidated balance sheet at December 31, 2017 has been derived from the audited consolidated balance sheet at December 31, 2017 contained in the Form 10-K. Summary of Significant Accounting Policies During the three and six months ended June 30, 2018, there have been no changes to the Company’s significant accounting policies as described in the Form 10-K, except as described below. Accounts Receivable Accounts receivable are recorded net of customers’ allowances for prompt-pay discounts, chargebacks and doubtful accounts. Allowances for prompt-pay discounts and chargebacks are based on contractual terms. The Company estimates the allowance for doubtful accounts based on existing contractual payment terms, actual payment patterns of its customers and individual customer circumstances. At June 30, 2018, the Company did not have any allowances for doubtful accounts. Inventory Inventory is stated at the lower of cost or estimated net realizable value on a first-in, first-out (FIFO) basis. The Company periodically analyzes its inventory levels and writes down inventory as cost of product sales when: inventory has become obsolete; inventory has a cost basis in excess of its estimated net realizable value; or inventory quantities are in excess of expected sales. As of June 30, 2018, the Company had $0.9 million of inventory, which consisted of work in process of $0.2 million and finished goods of $0.7 million. Revenue Recognition The Company adopted the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 606 - Revenue from Contracts with Customers (ASC 606) at the time of its first commercial shipment of GIAPREZA in the first quarter of 2018. The Company had no revenue from product sales prior to the first quarter of 2018. Under ASC 606, the Company recognizes revenue when distributors (our customers) obtain control of the Company’s product, which typically occurs on delivery. Revenue is recognized in an amount that reflects the consideration that the Company expects to receive in exchange for those goods. To determine revenue recognition for contracts with customers within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. Revenue from product sales is recorded at the transaction price, net of estimates for variable consideration consisting of chargebacks, discounts, returns and other allowances offered to our customers. Variable consideration is estimated using the most-likely amount method, which is the single-most likely outcome under a contract and is typically at the stated contractual rate. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results vary materially from the Company’s estimates, the Company will adjust these estimates, which will affect revenue from product sales and earnings in the period such estimates are adjusted. Chargebacks. Chargebacks are discounts the Company provides to distributors in the event that the sales prices to end users are below the distributors’ acquisition price. Chargebacks are estimated based on known chargeback rates and recorded as a reduction of revenue upon delivery to the Company’s customers. Discounts. The Company offers customers various forms of incentives and consideration, including prompt-pay discounts, service fees and other contract fees. The Company estimates discounts and fees primarily based on contractual terms. These discounts and fees are recorded as a reduction of revenue upon delivery to the Company’s customers. Returns. The Company offers customers a limited right of return, generally for damaged or expired product. The Company estimates returns based on an internal analysis, which includes actual experience and a review of comparable companies. The estimates for returns are recorded as a reduction of revenue upon delivery to the Company’s customers. The Company will continue to assess its estimates of variable consideration as it accumulates additional historical data and will adjust these estimates accordingly. Interest Expense Interest expense and the amortization of debt issuance costs related to the deferred royalty obligation (see Note 5) are recognized over the expected repayment term of the deferred royalty obligation using the effective interest method. The assumptions used in determining the expected repayment term of the deferred royalty obligation require the Company to make estimates that could impact the effective interest rate. Each reporting period, the Company estimates the expected repayment term of the deferred royalty obligation based on forecasted net product sales of GIAPREZA. Changes in interest expense resulting from changes in the effective interest rate, if any, are recorded on a prospective basis. Net Loss per Share Basic net loss per share is calculated based on the weighted-average number of common shares outstanding. Diluted net loss per share is calculated based on the weighted-average number of common shares outstanding plus common stock equivalents. Convertible preferred stock, stock options and warrants are considered common stock equivalents and are included in the calculation of diluted net loss per share using the treasury stock method when their effect is dilutive. Common stock equivalents are excluded from the calculation of diluted net loss per share when their effect is anti-dilutive. As of June 30, 2018 and 2017, there were 14.2 million shares and 11.5 million shares, respectively, of common stock equivalents, which were excluded from the calculation of diluted net loss per share because their effect was anti-dilutive. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In the first quarter of 2018, the Company adopted Accounting Standard Update (ASU) 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. The standard clarifies the presentation of restricted cash and cash equivalents and requires companies to include restricted cash and cash equivalents in the beginning and ending balances of cash and cash equivalents on the statement of cash flows. The standard also requires additional disclosures to describe the amount and detail of the restriction by balance sheet line item. Accordingly, restricted cash is included as a component of cash, cash equivalents and restricted cash in the unaudited condensed consolidated statement of cash flows for all periods presented, and we have disclosed the amount and detail of the restriction by balance sheet line item. Not Yet Adopted Accounting Pronouncements In June 2018, the FASB issued ASU 2018-07, Stock Compensation (Topic 718): Improvements to Nonemployee Share-based Payment Accounting. The standard expands the scope of ASC 718 to include share-based payments granted to nonemployees in exchange for goods and services. The provisions of this standard are effective for annual periods beginning after December 15, 2018, and for interim periods within those years. Early adoption is permitted. The Company will adopt the standard in the first quarter of 2019. The Company is currently evaluating the impact of this standard on it consolidated financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The standard requires lessees to recognize right-of-use assets and lease liabilities for most leases. The provisions of this standard are effective for annual periods beginning after December 15, 2018, and for interim periods within those years; early adoption is permitted. The Company will adopt the standard in the first quarter of 2019 using the modified retrospective approach. Although the Company is in the process of evaluating the impact of adoption of the standard on its consolidated financial statements, the Company currently believes the most significant changes will be related to the recognition of a new right-of-use asset and lease liability on the balance sheet for its 10-year operating lease agreement for its corporate headquarters, which commenced October 30, 2017.

Summary of Significant Accounting Policies

Basis of Presentation and Use of Estimates

The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of the SEC Regulation S-X. Accordingly, they should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2017 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017, filed with the SEC on February 22, 2018 (the Form 10-K). The accompanying unaudited condensed consolidated financial statements include the accounts of La Jolla Pharmaceutical Company and its wholly-owned subsidiaries. All significant inter-company transactions and balances have been eliminated in consolidation. The unaudited condensed consolidated financial statements contain all normal recurring accruals and adjustments that, in the opinion of management, are necessary to present fairly the condensed consolidated balance sheet of the Company at June 30, 2018, the condensed consolidated statement of operations for the three and six months ended June 30, 2018 and the condensed consolidated statement of cash flows for the six months ended June 30, 2018.

The preparation of the Company’s unaudited condensed consolidated financial statements requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities, revenue and expenses and the disclosure of contingent assets and liabilities in the Company’s unaudited condensed consolidated financial statements and the accompanying notes. Actual results could differ materially from those estimates. The results of operations for the three and six months ended June 30, 2018 are not necessarily indicative of the results to be expected for the full year or any future interim periods. The accompanying condensed consolidated balance sheet at December 31, 2017 has been derived from the audited consolidated balance sheet at December 31, 2017 contained in the Form 10-K.

Summary of Significant Accounting Policies

During the three and six months ended June 30, 2018, there have been no changes to the Company’s significant accounting policies as described in the Form 10-K, except as described below.

Accounts Receivable

Accounts receivable are recorded net of customers’ allowances for prompt-pay discounts, chargebacks and doubtful accounts. Allowances for prompt-pay discounts and chargebacks are based on contractual terms. The Company estimates the allowance for doubtful accounts based on existing contractual payment terms, actual payment patterns of its customers and individual customer circumstances. At June 30, 2018, the Company did not have any allowances for doubtful accounts.

Inventory

Inventory is stated at the lower of cost or estimated net realizable value on a first-in, first-out (FIFO) basis. The Company periodically analyzes its inventory levels and writes down inventory as cost of product sales when: inventory has become obsolete; inventory has a cost basis in excess of its estimated net realizable value; or inventory quantities are in excess of expected sales. As of June 30, 2018, the Company had $0.9 million of inventory, which consisted of work in process of $0.2 million and finished goods of $0.7 million.

Revenue Recognition

The Company adopted the Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 606 - Revenue from Contracts with Customers (ASC 606) at the time of its first commercial shipment of GIAPREZA in the first quarter of 2018. The Company had no revenue from product sales prior to the first quarter of 2018.

Under ASC 606, the Company recognizes revenue when distributors (our customers) obtain control of the Company’s product, which typically occurs on delivery. Revenue is recognized in an amount that reflects the consideration that the Company expects to receive in exchange for those goods. To determine revenue recognition for contracts with customers within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation.

Revenue from product sales is recorded at the transaction price, net of estimates for variable consideration consisting of chargebacks, discounts, returns and other allowances offered to our customers. Variable consideration is estimated using the most-likely amount method, which is the single-most likely outcome under a contract and is typically at the stated contractual rate. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results vary materially from the Company’s estimates, the Company will adjust these estimates, which will affect revenue from product sales and earnings in the period such estimates are adjusted.

Chargebacks. Chargebacks are discounts the Company provides to distributors in the event that the sales prices to end users are below the distributors’ acquisition price. Chargebacks are estimated based on known chargeback rates and recorded as a reduction of revenue upon delivery to the Company’s customers.

Discounts. The Company offers customers various forms of incentives and consideration, including prompt-pay discounts, service fees and other contract fees. The Company estimates discounts and fees primarily based on contractual terms. These discounts and fees are recorded as a reduction of revenue upon delivery to the Company’s customers.

Returns. The Company offers customers a limited right of return, generally for damaged or expired product. The Company estimates returns based on an internal analysis, which includes actual experience and a review of comparable companies. The estimates for returns are recorded as a reduction of revenue upon delivery to the Company’s customers.

The Company will continue to assess its estimates of variable consideration as it accumulates additional historical data and will adjust these estimates accordingly.

Interest Expense

Interest expense and the amortization of debt issuance costs related to the deferred royalty obligation (see Note 5) are recognized over the expected repayment term of the deferred royalty obligation using the effective interest method. The assumptions used in determining the expected repayment term of the deferred royalty obligation require the Company to make estimates that could impact the effective interest rate. Each reporting period, the Company estimates the expected repayment term of the deferred royalty obligation based on forecasted net product sales of GIAPREZA. Changes in interest expense resulting from changes in the effective interest rate, if any, are recorded on a prospective basis.

Net Loss per Share

Basic net loss per share is calculated based on the weighted-average number of common shares outstanding. Diluted net loss per share is calculated based on the weighted-average number of common shares outstanding plus common stock equivalents. Convertible preferred stock, stock options and warrants are considered common stock equivalents and are included in the calculation of diluted net loss per share using the treasury stock method when their effect is dilutive. Common stock equivalents are excluded from the calculation of diluted net loss per share when their effect is anti-dilutive. As of June 30, 2018 and 2017, there were 14.2 million shares and 11.5 million shares, respectively, of common stock equivalents, which were excluded from the calculation of diluted net loss per share because their effect was anti-dilutive.

Recent Accounting Pronouncements

Recently Adopted Accounting Pronouncements

In the first quarter of 2018, the Company adopted Accounting Standard Update (ASU) 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. The standard clarifies the presentation of restricted cash and cash equivalents and requires companies to include restricted cash and cash equivalents in the beginning and ending balances of cash and cash equivalents on the statement of cash flows. The standard also requires additional disclosures to describe the amount and detail of the restriction by balance sheet line item. Accordingly, restricted cash is included as a component of cash, cash equivalents and restricted cash in the unaudited condensed consolidated statement of cash flows for all periods presented, and we have disclosed the amount and detail of the restriction by balance sheet line item.

Not Yet Adopted Accounting Pronouncements

In June 2018, the FASB issued ASU 2018-07, Stock Compensation (Topic 718): Improvements to Nonemployee Share-based Payment Accounting. The standard expands the scope of ASC 718 to include share-based payments granted to nonemployees in exchange for goods and services. The provisions of this standard are effective for annual periods beginning after December 15, 2018, and for interim periods within those years. Early adoption is permitted. The Company will adopt the standard in the first quarter of 2019. The Company is currently evaluating the impact of this standard on it consolidated financial statements and disclosures.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The standard requires lessees to recognize right-of-use assets and lease liabilities for most leases. The provisions of this standard are effective for annual periods beginning after December 15, 2018, and for interim periods within those years; early adoption is permitted. The Company will adopt the standard in the first quarter of 2019 using the modified retrospective approach. Although the Company is in the process of evaluating the impact of adoption of the standard on its consolidated financial statements, the Company currently believes the most significant changes will be related to the recognition of a new right-of-use asset and lease liability on the balance sheet for its 10-year operating lease agreement for its corporate headquarters, which commenced October 30, 2017.