Summary of Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2012
Basis of Consolidation	Basis of Consolidation. The consolidated financial statements include the accounts of the Company and Galectin Therapeutics Security Corp., its wholly-owned subsidiary, which was incorporated in Delaware on December 23, 2003. Galectin Therapeutics Security Corp. holds the cash and cash equivalents that are not required to fund current operating needs. All intercompany transactions have been eliminated.
Use of Estimates	Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and judgments that may affect the reported amounts of assets, liabilities, equity, revenue, expenses and related disclosure of contingent assets and liabilities. Management’s estimates and judgments include assumptions used in stock option and warrant liability valuations, useful lives of property and equipment and intangible assets, accrued liabilities, deferred income taxes and various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions.
Fair Value Measurements	Fair Value Measurements. The Company has certain financial assets and liabilities recorded at fair value. Fair values determined by Level 1 inputs utilize observable data such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points in which there is little or no market data, which require the reporting entity to develop its own assumptions. The estimated value of accounts payable and accrued expenses approximates their carrying value due to their short-term nature using level 3 inputs as defined above. Included in cash and cash equivalents, as of December 31, 2012 and 2011, the Company had $583,000 and $6,123,000, respectively, invested in money market funds which had calculated net asset values and were therefore classified as Level 2.
Cash and Cash Equivalents	Cash and Cash Equivalents. The Company considers all highly-liquid investments with original maturities of 90 days or less at the time of acquisition to be cash equivalents.
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets. Prepaid expenses and other assets consist principally of prepaid insurance and prepaid rent on the Company’s leased executive office space.
Property and Equipment	Property and Equipment. Property and equipment, including leasehold improvements, are stated at cost, net of accumulated depreciation, and are depreciated using the straight-line method over the estimated useful lives of the related assets of generally three years for computers and office equipment, five years for furniture and fixtures and the shorter of the useful life or life of the lease for leasehold improvements.
Restricted Cash and Security Deposit	Restricted Cash and Security Deposit. Restricted cash consists of security deposits principally for a real estate lease at December 31, 2011. At December 31, 2012, the Company had a security deposit of $6,000 for leased office space.
Intangible Assets	Intangible Assets. Intangible assets include patent costs, consisting primarily of related capitalized legal fees, which are amortized over an estimated useful life of five years from issuance. Amortization expense in 2012 and 2011 was $6,000 and $3,000, respectively. Gross intangible assets at December 31, 2012 and 2011 totaled $78,000 each year, and accumulated amortization at December 31, 2012 and 2011 totaled $48,000 and $42,000, respectively.
Long-Lived Assets	Long-Lived Assets. The Company reviews all long-lived assets for impairment whenever events or circumstances indicate the carrying amount of such assets may not be recoverable. Recoverability of assets to be held or used is measured by comparison of the carrying value of the asset to the future undiscounted net cash flows expected to be generated by the asset. If such asset is considered to be impaired, the impairment recognized is measured by the amount by which the carrying value of the asset exceeds the discounted future cash flows expected to be generated by the asset.
Warrants	Warrants. The Company has issued common stock warrants in connection with the execution of certain equity and debt financings. Certain warrants were accounted for as derivative liabilities at fair value. Such warrants did not meet the accounting criteria that a contract should not be considered a derivative instrument if it is (1) indexed to its own stock and (2) classified in stockholders’ equity. Changes in fair value of derivative liabilities are recorded in the consolidated statement of operations under the caption “Change in fair value of warrant liabilities.” Warrants that are not considered derivative liabilities are accounted for at fair value at the date of issuance in additional paid-in capital. The fair value of warrants was determined using the Black-Scholes option-pricing model. There were no warrant liabilities as of December 31, 2012 or 2011.
Revenue Recognition	Revenue Recognition. The Company records revenue provided that there is persuasive evidence that an arrangement exists, the price is fixed and determinable, services were rendered and collectability is reasonably assured.
Research and Development Expenses	Research and Development Expenses. Costs associated with research and development are expensed as incurred. Research and development expenses include, among other costs, salaries and other personnel-related costs, and costs incurred by outside laboratories and other accredited facilities in connection with clinical trials and preclinical studies.
Income Taxes	Income Taxes. The Company accounts for income taxes in accordance with the accounting rules that requires an asset and liability approach to accounting for income taxes based upon the future expected values of the related assets and liabilities. Deferred income tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and for tax loss and credit carry forwards, and are measured using the expected tax rates estimated to be in effect when such basis differences reverse. Valuation allowances are established, if necessary, to reduce the deferred tax asset to the amount that will, more likely than not, be realized.
Comprehensive Income (Loss)	Comprehensive Income (Loss). Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company does not have any items of comprehensive income (loss) other than net losses as reported.
Concentration of Credit Risk	Concentration of Credit Risk. Financial instruments that subject the Company to credit risk consist of cash and cash equivalents and certificates of deposit. The Company maintains cash and cash equivalents and certificates of deposit with well-capitalized financial institutions. At times, those amounts may exceed federally insured limits. The Company has no significant concentrations of credit risk.
Stock-Based Compensation	Stock-Based Compensation. Stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the service period, which generally represents the vesting period. For awards that have performance based vesting conditions the Company recognizes the expense over the estimated period that the awards are expected to be earned. The Company generally uses the Black-Scholes option-pricing model to calculate the grant date fair value of stock options. For options that only vest upon the achievement of market conditions, the Company values the options using a Monte Carlo model to calculate the grant date fair value of the stock options. The expense related to options that vest based on market conditions is not reversed should those options not ultimately vest. The expense recognized over the service period is required to include an estimate of the awards that will be forfeited.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2012

Basis of Consolidation. The consolidated financial statements include the accounts of the Company and Galectin Therapeutics Security Corp., its wholly-owned subsidiary, which was incorporated in Delaware on December 23, 2003. Galectin Therapeutics Security Corp. holds the cash and cash equivalents that are not required to fund current operating needs. All intercompany transactions have been eliminated.

Use of Estimates

Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and judgments that may affect the reported amounts of assets, liabilities, equity, revenue, expenses and related disclosure of contingent assets and liabilities. Management’s estimates and judgments include assumptions used in stock option and warrant liability valuations, useful lives of property and equipment and intangible assets, accrued liabilities, deferred income taxes and various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions.

Fair Value Measurements

Fair Value Measurements. The Company has certain financial assets and liabilities recorded at fair value. Fair values determined by Level 1 inputs utilize observable data such as quoted prices in active markets. Fair values determined by Level 2 inputs utilize data points other than quoted prices in active markets that are observable either directly or indirectly. Fair values determined by Level 3 inputs utilize unobservable data points in which there is little or no market data, which require the reporting entity to develop its own assumptions. The estimated value of accounts payable and accrued expenses approximates their carrying value due to their short-term nature using level 3 inputs as defined above. Included in cash and cash equivalents, as of December 31, 2012 and 2011, the Company had $583,000 and $6,123,000, respectively, invested in money market funds which had calculated net asset values and were therefore classified as Level 2.

Cash and Cash Equivalents

Cash and Cash Equivalents. The Company considers all highly-liquid investments with original maturities of 90 days or less at the time of acquisition to be cash equivalents.

Prepaid Expenses and Other Current Assets

Prepaid Expenses and Other Current Assets. Prepaid expenses and other assets consist principally of prepaid insurance and prepaid rent on the Company’s leased executive office space.

Property and Equipment

Property and Equipment. Property and equipment, including leasehold improvements, are stated at cost, net of accumulated depreciation, and are depreciated using the straight-line method over the estimated useful lives of the related assets of generally three years for computers and office equipment, five years for furniture and fixtures and the shorter of the useful life or life of the lease for leasehold improvements.

Restricted Cash and Security Deposit

Restricted Cash and Security Deposit. Restricted cash consists of security deposits principally for a real estate lease at December 31, 2011. At December 31, 2012, the Company had a security deposit of $6,000 for leased office space.

Intangible Assets

Intangible Assets. Intangible assets include patent costs, consisting primarily of related capitalized legal fees, which are amortized over an estimated useful life of five years from issuance. Amortization expense in 2012 and 2011 was $6,000 and $3,000, respectively. Gross intangible assets at December 31, 2012 and 2011 totaled $78,000 each year, and accumulated amortization at December 31, 2012 and 2011 totaled $48,000 and $42,000, respectively.

Long-Lived Assets

Long-Lived Assets. The Company reviews all long-lived assets for impairment whenever events or circumstances indicate the carrying amount of such assets may not be recoverable. Recoverability of assets to be held or used is measured by comparison of the carrying value of the asset to the future undiscounted net cash flows expected to be generated by the asset. If such asset is considered to be impaired, the impairment recognized is measured by the amount by which the carrying value of the asset exceeds the discounted future cash flows expected to be generated by the asset.

Warrants

Warrants. The Company has issued common stock warrants in connection with the execution of certain equity and debt financings. Certain warrants were accounted for as derivative liabilities at fair value. Such warrants did not meet the accounting criteria that a contract should not be considered a derivative instrument if it is (1) indexed to its own stock and (2) classified in stockholders’ equity. Changes in fair value of derivative liabilities are recorded in the consolidated statement of operations under the caption “Change in fair value of warrant liabilities.” Warrants that are not considered derivative liabilities are accounted for at fair value at the date of issuance in additional paid-in capital. The fair value of warrants was determined using the Black-Scholes option-pricing model. There were no warrant liabilities as of December 31, 2012 or 2011.

Revenue Recognition

Revenue Recognition. The Company records revenue provided that there is persuasive evidence that an arrangement exists, the price is fixed and determinable, services were rendered and collectability is reasonably assured.

Research and Development Expenses

Research and Development Expenses. Costs associated with research and development are expensed as incurred. Research and development expenses include, among other costs, salaries and other personnel-related costs, and costs incurred by outside laboratories and other accredited facilities in connection with clinical trials and preclinical studies.

Income Taxes

Income Taxes. The Company accounts for income taxes in accordance with the accounting rules that requires an asset and liability approach to accounting for income taxes based upon the future expected values of the related assets and liabilities. Deferred income tax assets and liabilities are determined based on the differences between the financial reporting and tax bases of assets and liabilities and for tax loss and credit carry forwards, and are measured using the expected tax rates estimated to be in effect when such basis differences reverse. Valuation allowances are established, if necessary, to reduce the deferred tax asset to the amount that will, more likely than not, be realized.

Comprehensive Income (Loss)

Comprehensive Income (Loss). Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company does not have any items of comprehensive income (loss) other than net losses as reported.

Concentration of Credit Risk

Concentration of Credit Risk. Financial instruments that subject the Company to credit risk consist of cash and cash equivalents and certificates of deposit. The Company maintains cash and cash equivalents and certificates of deposit with well-capitalized financial institutions. At times, those amounts may exceed federally insured limits. The Company has no significant concentrations of credit risk.

Stock-Based Compensation

Stock-Based Compensation. Stock-based compensation cost is measured at the grant date based on the fair value of the award and is recognized as expense over the service period, which generally represents the vesting period. For awards that have performance based vesting conditions the Company recognizes the expense over the estimated period that the awards are expected to be earned. The Company generally uses the Black-Scholes option-pricing model to calculate the grant date fair value of stock options. For options that only vest upon the achievement of market conditions, the Company values the options using a Monte Carlo model to calculate the grant date fair value of the stock options. The expense related to options that vest based on market conditions is not reversed should those options not ultimately vest. The expense recognized over the service period is required to include an estimate of the awards that will be forfeited.