Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2021
Accounting Policies [Abstract]
Principles of Consolidation	Principles of ConsolidationThe Condensed Consolidated Financial Statements include the accounts of the Company, its wholly owned subsidiaries and all other subsidiaries over which the Company exerts control. All intercompany profits, transactions and balances have been eliminated in consolidation. As of June 30, 2021, the results of DBMG, Genovel, R2, HC2 Broadcasting, CIG, GMH and Beyond6 have been consolidated into the Company’s results based on guidance from the Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC" 810, Consolidation). The remaining interests not owned by the Company are presented as a noncontrolling interest component of total equity.
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of the Company included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC"). The financial statements reflect all adjustments that are, in the opinion of management, necessary for a fair statement of such information. All such adjustments are of a normal recurring nature. Certain information and note disclosures, including a description of significant accounting policies normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP"), have been condensed or omitted pursuant to such rules and regulations. Certain prior amounts have been reclassified or combined to conform to the current year presentation. These interim financial statements should be read in conjunction with the Company’s annual Consolidated Financial Statements and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020, filed with the SEC on March 10, 2021. The results of operations for the three and six months ended June 30, 2021 are not necessarily indicative of the results for any subsequent periods or the entire fiscal year ending December 31, 2021.
Use of Estimates and Assumptions	Use of Estimates and Assumptions The preparation of the Company’s Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates and assumptions used.
Reclassification	Reclassification Certain previous year amounts have been reclassified to conform with current year presentations, as related to the reporting of new balance sheet line items: •The recast of Beyond6, ICS, and CIG's results to discontinued operations. Further, the reclassification of prior period assets and liabilities have been classified as held for sale. See Note 3. Discontinued Operations for further information; •As a result of the sale of ICS, and in accordance with ASC 280, the Company no longer considers the results of operations and Balance Sheets of the retained ICS entities as a separate segment. Formerly the Telecommunications segment, these entities have been reclassified to the Other segment. See Note 17. Operating Segment and Related Information for further information; •As a result of the sale of Beyond6, and in accordance with ASC 280, the Company no longer considers the results of operations and Balance Sheets of Beyond6 as a separate segment. Formerly the Clean Energy segment, this entity has been reclassified to the Other segment. See Note 17. Operating Segment and Related Information for further information; and •The recast of prior year earnings per share as a result of the discontinued operations noted above. This includes presenting EPS for Net income (loss) from continuing operations, Net income (loss) from discontinuing operations, and Net income (loss). See Note 18. Basic and Diluted Income (Loss) Per Common Share for further details. •Certain 2021 statement of cash flow items have been reclassified to conform to the current financial statement presentation. These reclassifications have no effect on previously reported net income.
Accounting Pronouncements	Accounting Pronouncements Adopted in the Current Year Accounting for Debt with Conversion Options ASU 2020-06, Debt - Debt with Conversion and Other Options (Subtopic 470- 20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, was issued by the FASB in August 2020. This ASU (1) simplifies the accounting for convertible debt instruments and convertible preferred stock by removing the existing guidance in ASC 470-20, Debt: Debt with Conversion and Other Options, that requires entities to account for beneficial conversion features and cash conversion features in equity, separately from the host convertible debt or preferred stock; (2) revises the scope exception from derivative accounting in ASC 815-40 for freestanding financial instruments and embedded features that are both indexed to the issuer’s own stock and classified in stockholders’ equity, by removing certain criteria required for equity classification; and (3) revises the guidance in ASC 260, Earnings Per Share, to require entities to calculate diluted earnings per share (EPS) for convertible instruments by using the if-converted method. In addition, entities must presume share settlement for purposes of calculating diluted EPS when an instrument may be settled in cash or shares. The standard is effective on January 1, 2024, but early adoption was elected as of January 1, 2021. A modified retrospective method of transition was applied, which resulted in no impact to the Company. Accounting Pronouncements to be Adopted Subsequent to December 31, 2021 Credit Loss Standard ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments, was issued by FASB in June 2016. This standard is effective January 1, 2020 (with early adoption permitted). This new standard changes the impairment model for most financial assets that are measured at amortized cost and certain other instruments, including trade receivables, from an incurred loss model to an expected loss model and adds certain new required disclosures. Under the expected loss model, entities will recognize estimated credit losses over the entire contractual term of the instrument rather than delaying recognition of credit losses until it is probable the loss has been incurred. The FASB has voted to delay the effective date of ASU 2016-13 to January 1, 2023 for smaller reporting companies with a revised ASU in the fourth quarter of 2019. The Company will not be required to adopt Topic 326 until January 1, 2023. Currently, the Company continues to evaluate the potential impact of the new standard on its financial results. Subsequent Events ASC 855, Subsequent Events requires the Company to evaluate events that occur after the balance sheet date as of which the financial statements are issued, and to determine whether adjustments to or additional disclosures in the financial statements are necessary.