General (Policies)	3 Months Ended
General (Policies)	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	The accompanying consolidated balance sheet as of December 31, 2020, which is derived from audited financial statements, and the unaudited consolidated financial statements, including the notes thereto, include the accounts of FirstCash, Inc. and its wholly-owned subsidiaries (together, the “Company”). The Company regularly makes acquisitions and the results of operations for the acquired stores have been consolidated since the acquisition dates. All significant intercompany accounts and transactions have been eliminated. These unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and with the rules and regulations for reporting on Form 10-Q. Accordingly, they do not include certain information and disclosures required for comprehensive financial statements. These interim period financial statements should be read in conjunction with the Company’s consolidated financial statements, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, filed with the Securities and Exchange Commission (the “SEC”) on February 1, 2021. The consolidated financial statements as of March 31, 2021 and 2020, and for the three month periods ended March 31, 2021 and 2020, are unaudited, but in management’s opinion include all adjustments (consisting of only normal recurring adjustments) considered necessary to present fairly the financial position, results of operations and cash flow for such interim periods. Operating results for the period ended March 31, 2021 are not necessarily indicative of the results that may be expected for the full year. The Company has operations in Latin America, where in Mexico, Guatemala and Colombia, the functional currency is the Mexican peso, Guatemalan quetzal and Colombian peso. Accordingly, the assets and liabilities of these subsidiaries are translated into U.S. dollars at the exchange rate in effect at each balance sheet date, and the resulting adjustments are accumulated in other comprehensive income (loss) as a separate component of stockholders’ equity. Revenues and expenses are translated at the average exchange rates occurring during the respective period. The Company also has operations in El Salvador where the reporting and functional currency is the U.S. dollar.
Recent Accounting Pronouncements	In December 2019, the Financial Accounting Standards Board issued ASU No 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 removes certain exceptions to the general principles in Topic 740 in Generally Accepted Accounting Principles. ASU 2019-12 is effective for public entities for fiscal years beginning after December 15, 2020, with early adoption permitted. The adoption of ASU 2019-12 did not have a material effect on the Company’s current financial position, results of operations or financial statement disclosures. In March 2020, the Financial Accounting Standards Board issued ASU No 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting” (“ASU 2020-04”). ASU 2020-04 provides temporary optional expedients and exceptions to the GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates. ASU 2020-04 is effective beginning on March 12, 2020, and the Company may elect to apply the amendments prospectively through December 31, 2022. The Company does not expect ASU 2020-04 to have a material effect on the Company’s current financial position, results of operations or financial statement disclosures.
Fair Value Measurement	The fair value of financial instruments is determined by reference to various market data and other valuation techniques, as appropriate. Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of the fair value of assets and liabilities and their placement within the fair value hierarchy levels. The three fair value levels are (from highest to lowest): Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data.