The buildings that serve as collateral for Lexicon's mortgage loan.

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Contractual interest rate for funds borrowed under convertible debt, under the debt agreement.

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The land that serves as collateral for Lexicon's mortgage loan.

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Minimum XERMELO sales to draw Tranche B - represents the minimum sales in a quarter that must be met by the Company before March 19, 2019 in order to draw $50 million on the debt agreement entered into during December 2017

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Tranche B debt - Represents the second tranche of debt available for draw by March 19, 2019 at the Company's option if net XERMELO sales are greater than $25 million in the preceding quarter

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In April 2004, Lexicon purchased its existing laboratory and office buildings and animal facilities in The Woodlands, Texas with proceeds from a $34.0 million third-party mortgage financing and $20.8 million in cash. This represents the $20.8 million cash paid.

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WoodlandsMortgageInterestRate interest rate on mortgage loan for Woodlands building and land

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Identification of the lender and information about a contractual promise to repay a short-term or long-term obligation, which includes borrowings under lines of credit, notes payable, commercial paper, bonds payable, debentures, and other contractual obligations for payment. This may include rationale for entering into the arrangement, significant terms of the arrangement, which may include amount, repayment terms, priority, collateral required, debt covenants, borrowing capacity, call features, participation rights, conversion provisions, sinking-fund requirements, voting rights, basis for conversion if convertible and remarketing provisions. The description may be provided for individual debt instruments, rational groupings of debt instruments, or by debt in total.

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Face (par) amount of debt instrument at time of issuance.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The carrying amount of the outstanding balance due under the mortgage loan.

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The total of the cash outflow during the period which has been paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt and the cost incurred directly for the issuance of equity securities.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt Obligations (Details 2) $ / shares in Units, $ in Millions	1 Months Ended
	Dec. 31, 2017 USD ($) $ / shares	Nov. 30, 2014 USD ($)	Apr. 30, 2004 USD ($)	Dec. 18, 2017 USD ($)
Debt Instrument
Proceeds from Convertible Debt		$ 87.5
Convertible Debt Instrument Interest Rate Stated Percentage	5.25%
Debt Instrument, Convertible, Conversion Ratio		118.4553
Debt Instrument, Convertible, Conversion Price \| $ / shares	$ 8.442
Debt Issuance Cost		$ 3.4
Unamortized Debt Issuance Expense	$ 1.9
Debt Instrument, Fair Value Disclosure	$ 127.3
Woodlands Mortgage			$ 34.0
Woodlands Cash Paid			$ 20.8
WoodlandsMortgageInterestRate	8.23%
Debt Instrument, Interest Rate, Stated Percentage	9.00%
Mortgage Loans on Real Estate, Carrying Amount of Mortgages	$ 14.1
Buildings Collateral	59.2
Land Collateral	$ 2.7
Debt Instrument, Description	200000
Debt Instrument, Face Amount				$ 150.0
Tranche B debt	$ 50.0
Minimum XERMELO sales to draw Tranche B	$ 25.0
Debt Issuance Costs, Gross				$ 4.1