Basis of Presentation (Policies)	3 Months Ended
Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Principles of Consolidation	The interim consolidated financial statements of Merit Medical Systems, Inc. ("Merit," "we" or "us") for the three-month periods ended March 31, 2019 and 2018 are not audited. Our consolidated financial statements are prepared in accordance with the requirements for unaudited interim periods and, consequently, do not include all disclosures required to be made in conformity with accounting principles generally accepted in the United States of America. In the opinion of our management, the accompanying consolidated financial statements contain all adjustments, consisting of normal recurring accruals, necessary for a fair presentation of our financial position as of March 31, 2019 and December 31, 2018, and our results of operations and cash flows for the three-month periods ended March 31, 2019 and 2018. The results of operations for the three-month periods ended March 31, 2019 and 2018 are not necessarily indicative of the results for a full-year period. These interim consolidated financial statements should be read in conjunction with the financial statements included in our Annual Report on Form 10-K (the "2018 Form 10-K") for the year ended December 31, 2018, which was filed with the Securities and Exchange Commission (the "SEC") on March 1, 2019.
Revenue from Contracts with Customers	Revenue from Contracts with Customers. In accordance with Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASC 606"), we recognize revenue when a customer obtains control of promised goods. The amount of revenue recognized reflects the consideration we expect to receive in exchange for these goods.
Recently Issued Financial Accounting Standards	Recently Issued Financial Accounting Standards. Recently Adopted In February 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) ("ASC 842"), which requires lessees to recognize right-of-use ("ROU") assets and related lease liabilities on the balance sheet for all leases greater than one year in duration. We adopted ASC 842 on January 1, 2019 using a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The modified retrospective approach did not require any transition accounting for leases that expired before the earliest comparative period presented. The adoption of this standard resulted in the recording of ROU assets and lease liabilities for all of our lease agreements with original terms of greater than one year. The adoption of ASC 842 did not have a significant impact on our consolidated statements of operations or cash flows. See Note 14 for the required disclosures relating to our lease agreements. In June 2018, the FASB issued ASU 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, which simplifies the accounting for nonemployee share-based payment transactions by expanding the scope of ASC Topic 718, Compensation - Stock Compensation, to include share-based payment transactions for acquiring goods and services from nonemployees. Under the new standard, most of the guidance on stock compensation payments to nonemployees would be aligned with the requirements for share-based payments granted to employees. This standard became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements. In February 2018, the FASB issued ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from U.S. federal tax legislation commonly referred to as the Tax Cuts and Jobs Act, which was enacted in December 2017 (the "2017 Tax Act"). ASU 2018-02 became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands and refines hedge accounting for both financial and non-financial risk components, aligns the recognition and presentation of the effects of hedging instruments and hedge items in the financial statements, and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. ASU 2017-12 became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements. We do not believe any other issued and not yet effective accounting standards will be relevant to our consolidated financial statements.
Derivatives	Derivative Instruments Not Designated as Cash Flow Hedges We forecast our net exposure in various receivables and payables to fluctuations in the value of various currencies, and we enter into foreign currency forward contracts to mitigate that exposure.Derivatives. General. Our earnings and cash flows are subject to fluctuations due to changes in interest rates and foreign currency exchange rates, and we seek to mitigate a portion of these risks by entering into derivative contracts. The derivatives we use are interest rate swaps and foreign currency forward contracts. We recognize derivatives as either assets or liabilities at fair value in the accompanying consolidated balance sheets, regardless of whether or not hedge accounting is applied. We report cash flows arising from our hedging instruments consistent with the classification of cash flows from the underlying hedged items. Accordingly, cash flows associated with our derivative instruments are classified as operating activities in the accompanying consolidated statements of cash flows. We formally document, designate and assess the effectiveness of transactions that receive hedge accounting initially and on an ongoing basis. Changes in the fair value of derivatives that qualify for hedge accounting treatment are recorded, net of applicable taxes, in accumulated other comprehensive income (loss), a component of stockholders’ equity in the accompanying consolidated balance sheets. When the hedged transaction occurs, gains or losses are reclassified into earnings in the same line item associated with the forecasted transaction and in the same period or periods during which the hedged transaction affects earnings. Changes in the fair value of derivatives not designated as hedging instruments are recorded in earnings throughout the term of the derivative. Interest Rate Risk. A portion of our debt bears interest at variable interest rates and, therefore, we are subject to variability in the cash paid for interest expense. In order to mitigate a portion of this risk, we use a hedging strategy to reduce the variability of cash flows in the interest payments associated with a portion of the variable-rate debt outstanding under our Second Amended Credit Agreement that is solely due to changes in the benchmark interest rate.Balance Sheet Presentation of Derivative Instruments. As of March 31, 2019, and December 31, 2018, all derivative instruments, both those designated as hedging instruments and those that were not designated as hedging instruments, were recorded gross at fair value on our consolidated balance sheets. We are not subject to any master netting agreements. Foreign Currency Risk. We operate on a global basis and are exposed to the risk that our financial condition, results of operations, and cash flows could be adversely affected by changes in foreign currency exchange rates. To reduce the potential effects of foreign currency exchange rate movements on net earnings, we enter into derivative financial instruments in the form of foreign currency exchange forward contracts with major financial institutions. Our policy is to enter into foreign currency derivative contracts with maturities of up to two years. We are primarily exposed to foreign currency exchange rate risk with respect to transactions and balances denominated in Euros, British Pounds, Chinese Renminbi, Mexican Pesos, Brazilian Reals, Australian Dollars, Hong Kong Dollars, Swiss Francs, Swedish Krona, Canadian Dollars, Danish Krone, Japanese Yen, Korean Won, and Singapore Dollars. We do not use derivative financial instruments for trading or speculative purposes. We are not subject to any credit risk contingent features related to our derivative contracts, and counterparty risk is managed by allocating derivative contracts among several major financial institutions. Derivative Instruments Designated as Cash Flow Hedges We enter into forward contracts on various foreign currencies to manage the risk associated with forecasted exchange rates which impact revenues, cost of sales, and operating expenses in various international markets. The objective of the hedges is to reduce the variability of cash flows associated with the forecasted purchase or sale of the associated foreign currencies.

Basis of Presentation (Policies)

3 Months Ended

Mar. 31, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The interim consolidated financial statements of Merit Medical Systems, Inc. ("Merit," "we" or "us") for the three-month periods ended March 31, 2019 and 2018 are not audited. Our consolidated financial statements are prepared in accordance with the requirements for unaudited interim periods and, consequently, do not include all disclosures required to be made in conformity with accounting principles generally accepted in the United States of America. In the opinion of our management, the accompanying consolidated financial statements contain all adjustments, consisting of normal recurring accruals, necessary for a fair presentation of our financial position as of March 31, 2019 and December 31, 2018, and our results of operations and cash flows for the three-month periods ended March 31, 2019 and 2018. The results of operations for the three-month periods ended March 31, 2019 and 2018 are not necessarily indicative of the results for a full-year period. These interim consolidated financial statements should be read in conjunction with the financial statements included in our Annual Report on Form 10-K (the "2018 Form 10-K") for the year ended December 31, 2018, which was filed with the Securities and Exchange Commission (the "SEC") on March 1, 2019.

Revenue from Contracts with Customers

Revenue from Contracts with Customers.

In accordance with Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606) ("ASC 606"), we recognize revenue when a customer obtains control of promised goods. The amount of revenue recognized reflects the consideration we expect to receive in exchange for these goods.

Recently Issued Financial Accounting Standards

Recently Issued Financial Accounting Standards.

Recently Adopted

In February 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) ("ASC 842"), which requires lessees to recognize right-of-use ("ROU") assets and related lease liabilities on the balance sheet for all leases greater than one year in duration. We adopted ASC 842 on January 1, 2019 using a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The modified retrospective approach did not require any transition accounting for leases that expired before the earliest comparative period presented. The adoption of this standard resulted in the recording of ROU assets and lease liabilities for all of our lease agreements with original terms of greater than one year. The adoption of ASC 842 did not have a significant impact on our consolidated statements of operations or cash flows. See Note 14 for the required disclosures relating to our lease agreements.

In June 2018, the FASB issued ASU 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, which simplifies the accounting for nonemployee share-based payment transactions by expanding the scope of ASC Topic 718, Compensation - Stock Compensation, to include share-based payment transactions for acquiring goods and services from nonemployees. Under the new standard, most of the guidance on stock compensation payments to nonemployees would be aligned with the requirements for share-based payments granted to employees. This standard became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements.

In February 2018, the FASB issued ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from U.S. federal tax legislation commonly referred to as the Tax Cuts and Jobs Act, which was enacted in December 2017 (the "2017 Tax Act"). ASU 2018-02 became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements.

In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands and refines hedge accounting for both financial and non-financial risk components, aligns the recognition and presentation of the effects of hedging instruments and hedge items in the financial statements, and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. ASU 2017-12 became effective for us on January 1, 2019. The adoption of this standard did not have a material impact on our consolidated financial statements.

We do not believe any other issued and not yet effective accounting standards will be relevant to our consolidated financial statements.

Derivatives

Derivative Instruments Not Designated as Cash Flow Hedges

We forecast our net exposure in various receivables and payables to fluctuations in the value of various currencies, and we enter into foreign currency forward contracts to mitigate that exposure.Derivatives.

General. Our earnings and cash flows are subject to fluctuations due to changes in interest rates and foreign currency exchange rates, and we seek to mitigate a portion of these risks by entering into derivative contracts. The derivatives we use are interest rate swaps and foreign currency forward contracts. We recognize derivatives as either assets or liabilities at fair value in the accompanying consolidated balance sheets, regardless of whether or not hedge accounting is applied. We report cash flows arising from our hedging instruments consistent with the classification of cash flows from the underlying hedged items. Accordingly, cash flows associated with our derivative instruments are classified as operating activities in the accompanying consolidated statements of cash flows.

We formally document, designate and assess the effectiveness of transactions that receive hedge accounting initially and on an ongoing basis. Changes in the fair value of derivatives that qualify for hedge accounting treatment are recorded, net of applicable taxes, in accumulated other comprehensive income (loss), a component of stockholders’ equity in the accompanying consolidated balance sheets. When the hedged transaction occurs, gains or losses are reclassified into earnings in the same line item associated with the forecasted transaction and in the same period or periods during which the hedged transaction affects earnings. Changes in the fair value of derivatives not designated as hedging instruments are recorded in earnings throughout the term of the derivative.

Interest Rate Risk. A portion of our debt bears interest at variable interest rates and, therefore, we are subject to variability in the cash paid for interest expense. In order to mitigate a portion of this risk, we use a hedging strategy to reduce the variability of cash flows in the interest payments associated with a portion of the variable-rate debt outstanding under our Second Amended Credit Agreement that is solely due to changes in the benchmark interest rate.Balance Sheet Presentation of Derivative Instruments. As of March 31, 2019, and December 31, 2018, all derivative instruments, both those designated as hedging instruments and those that were not designated as hedging instruments, were recorded gross at fair value on our consolidated balance sheets. We are not subject to any master netting agreements.
Foreign Currency Risk. We operate on a global basis and are exposed to the risk that our financial condition, results of operations, and cash flows could be adversely affected by changes in foreign currency exchange rates. To reduce the potential effects of foreign currency exchange rate movements on net earnings, we enter into derivative financial instruments in the form of foreign currency exchange forward contracts with major financial institutions. Our policy is to enter into foreign currency derivative contracts with maturities of up to two years. We are primarily exposed to foreign currency exchange rate risk with respect to transactions and balances denominated in Euros, British Pounds, Chinese Renminbi, Mexican Pesos, Brazilian Reals, Australian Dollars, Hong Kong Dollars, Swiss Francs, Swedish Krona, Canadian Dollars, Danish Krone, Japanese Yen, Korean Won, and Singapore Dollars. We do not use derivative financial instruments for trading or speculative purposes. We are not subject to any credit risk contingent features related to our derivative contracts, and counterparty risk is managed by allocating derivative contracts among several major financial institutions.

Derivative Instruments Designated as Cash Flow Hedges

We enter into forward contracts on various foreign currencies to manage the risk associated with forecasted exchange rates which impact revenues, cost of sales, and operating expenses in various international markets. The objective of the hedges is to reduce the variability of cash flows associated with the forecasted purchase or sale of the associated foreign currencies.