Fair Value Measurement	6 Months Ended
Fair Value Measurement	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement MRV's financial instruments, including cash and cash equivalents, restricted time deposits, accounts receivable, other receivables included in other assets and accounts payable are carried at cost, which approximates their fair value. The fair value of accounts receivable and accounts payable approximate their carrying amounts due to their short-term nature. The Company follows a framework for measuring fair value using a three-level hierarchy that prioritizes the use of observable inputs. The fair value hierarchy is divided into three levels based on the source of inputs as follows: Level 1 - Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities; Level 2 - Valuations for which all significant inputs are observable, either directly or indirectly, other than level 1 inputs for similar instruments; Level 3 - Valuations based on inputs that are unobservable and significant to the overall fair value measurement. Under this framework, fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (i.e., the “exit price”) in an orderly transaction between market participants at the measurement date. Management has not elected the fair value option for non-financial assets and liabilities. MRV does not have any financial assets or liabilities that are re-measured at fair value on a recurring basis.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.