Greenlight Capital Re (GLRE) 10-Q 31 Jul 18 2018 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 27, 2018
Document and Entity Information [Line Items]
Entity Registrant Name	GREENLIGHT CAPITAL RE, LTD.
Entity Central Index Key	1,385,613
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common Class A
Document and Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		31,160,544
Common Class B
Document and Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		6,254,715

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Investments
Debt instruments, trading, at fair value	$ 13,831	$ 7,180
Equity securities, trading, at fair value	820,493	1,203,672
Other investments, at fair value	69,251	152,132
Total investments	903,575	1,362,984
Cash and cash equivalents	65,441	27,285
Restricted cash and cash equivalents	1,264,941	1,503,813
Financial contracts receivable, at fair value	68,123	12,893
Reinsurance balances receivable	321,873	301,762
Loss and loss adjustment expenses recoverable	37,005	29,459
Deferred acquisition costs, net	56,136	62,350
Unearned premiums ceded	28,735	25,120
Notes receivable, net	28,612	28,497
Other assets	4,327	3,230
Total assets	2,778,768	3,357,393
Liabilities
Securities sold, not yet purchased, at fair value	681,278	912,797
Financial contracts payable, at fair value	18,746	22,222
Due to prime brokers and other financial institutions	520,172	672,700
Loss and loss adjustment expense reserves	474,338	464,380
Unearned premium reserves	244,807	255,818
Reinsurance balances payable	147,096	144,058
Funds withheld	16,946	23,579
Other liabilities	7,284	10,413
Total liabilities	2,110,667	2,505,967
Redeemable non-controlling interest in related party joint venture	6,436	7,169
Equity
Preferred share capital (par value $0.10; authorized, 50,000,000; none issued)	0	0
Ordinary share capital (Class A: par value $0.10; authorized, 100,000,000; issued and outstanding, 31,160,544 (2017: 31,104,830): Class B: par value $0.10; authorized, 25,000,000; issued and outstanding, 6,254,715 (2017: 6,254,715))	3,742	3,736
Additional paid-in capital	503,331	503,316
Retained earnings	143,873	324,272
Shareholders’ equity attributable to shareholders	650,946	831,324
Non-controlling interest in related party joint venture	10,719	12,933
Total equity	661,665	844,257
Total liabilities, redeemable non-controlling interest and equity	$ 2,778,768	$ 3,357,393

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2018	Dec. 31, 2017
Stockholders’ Equity:
Preferred share capital, par value	$ 0.10	$ 0.10
Preferred share capital, authorized	50,000,000	50,000,000
Preferred share capital, issued	0	0
Common Class A
Stockholders’ Equity:
Ordinary share capital, par value (in dollars per share)	$ 0.10	$ 0.10
Ordinary share capital, authorized (in shares)	100,000,000	100,000,000
Ordinary share capital, issued (in shares)	31,160,544	31,104,830
Ordinary share capital, outstanding (in shares)	31,160,544	31,104,830
Common Class B
Stockholders’ Equity:
Ordinary share capital, par value (in dollars per share)	$ 0.10	$ 0.10
Ordinary share capital, authorized (in shares)	25,000,000	25,000,000
Ordinary share capital, issued (in shares)	6,254,715	6,254,715
Ordinary share capital, outstanding (in shares)	6,254,715	6,254,715

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues
Gross premiums written	$ 142,109	$ 174,889	$ 317,234	$ 372,103
Gross premiums ceded	(27,237)	(2,523)	(57,080)	(5,949)
Net premiums written	114,872	172,366	260,154	366,154
Change in net unearned premium reserves	13,944	(12,042)	14,506	(53,928)
Net premiums earned	128,816	160,324	274,660	312,226
Net investment income (loss) [net of related party expenses of $4,131, $3,148, $8,585 and $8,644]	(40,656)	(39,149)	(185,872)	(27,531)
Other income (expense), net	(76)	303	(563)	296
Total revenues	88,084	121,478	88,225	284,991
Expenses
Loss and loss adjustment expenses incurred, net	84,815	106,016	180,639	210,828
Acquisition costs, net	34,623	45,429	78,832	88,640
General and administrative expenses	6,958	6,347	12,914	13,090
Total expenses	126,396	157,792	272,385	312,558
Income (loss) before income tax	(38,312)	(36,314)	(184,160)	(27,567)
Income tax benefit	323	295	1,093	174
Net income (loss) including non-controlling interest	(37,989)	(36,019)	(183,067)	(27,393)
Loss (income) attributable to non-controlling interest in related party joint venture	621	550	2,947	298
Net income (loss)	$ (37,368)	$ (35,469)	$ (180,120)	$ (27,095)
Earnings (loss) per share
Basic	$ (1.01)	$ (0.96)	$ (4.87)	$ (0.73)
Diluted	$ (1.01)	$ (0.96)	$ (4.87)	$ (0.73)
Weighted average number of ordinary shares used in the determination of earnings and loss per share
Basic	36,952,472	37,025,703	36,950,828	37,009,539
Diluted	36,952,472	37,025,703	36,950,828	37,009,539

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Ordinary share capital	Additional paid-in capital	Retained earnings	Shareholders' equity attributable to shareholders	Non-controlling interest in joint venture
Balance at Dec. 31, 2016	$ 885,803	$ 3,737	$ 500,337	$ 370,168	$ 874,242	$ 11,561
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of Class A ordinary shares, net of forfeitures	11	11	0	0	11	0
Repurchase of Class A ordinary shares	(2,268)	(11)	(1,502)	(755)	(2,268)	0
Share-based compensation expense, net of forfeitures	1,847	0	1,847	0	1,847	0
Change in non-controlling interest in related party joint venture	219	0	0	0	0	219
Change in capital account allocation of non-controlling interest in related party joint venture	(298)
Net income (loss)	(27,095)	0	0	(27,095)	(27,095)	0
Balance at Jun. 30, 2017	858,517	3,737	500,682	342,318	846,737	11,780
Balance at Dec. 31, 2017	844,257	3,736	503,316	324,272	831,324	12,933
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issue of Class A ordinary shares, net of forfeitures	24	24	0	0	24	0
Repurchase of Class A ordinary shares	(2,753)	(18)	(2,456)	(279)	(2,753)	0
Share-based compensation expense, net of forfeitures	2,471	0	2,471	0	2,471	0
Change in non-controlling interest in related party joint venture	(2,214)	0	0	0	0	(2,214)
Change in capital account allocation of non-controlling interest in related party joint venture	(2,947)
Net income (loss)	(180,120)	0	0	(180,120)	(180,120)	0
Balance at Jun. 30, 2018	$ 661,665	$ 3,742	$ 503,331	$ 143,873	$ 650,946	$ 10,719

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 1,330,382	$ 1,394,500
Net income (loss)	(180,120)	(27,095)
Adjustments to reconcile net income or loss to net cash provided by (used in) operating activities
Net change in unrealized gains and losses on investments and financial contracts	56,890	81,253
Net realized (gains) losses on investments and financial contracts	129,147	(68,386)
Foreign exchange (gains) losses on investments	(167)	8,048
Income (loss) attributable to total non-controlling interest in related party joint venture	(2,947)	(298)
Share-based compensation expense, net of forfeitures	2,495	1,858
Depreciation expense	217	184
Net change in
Reinsurance balances receivable	(20,111)	(47,621)
Loss and loss adjustment expenses recoverable	(7,546)	43
Deferred acquisition costs, net	6,214	(17,194)
Unearned premiums ceded	(3,615)	(602)
Other assets	(1,314)	(2,128)
Loss and loss adjustment expense reserves	(9,958)	(52,714)
Unearned premium reserves	(11,011)	54,822
Reinsurance balances payable	3,038	13,954
Funds withheld	(6,633)	1,104
Other liabilities	(3,129)	(2,899)
Net cash provided by (used in) operating activities	(28,634)	47,757
Investing activities
Purchases of investments, trading	(252,600)	(518,595)
Sales of investments, trading	650,383	436,567
Payments for financial contracts	(112,532)	(15,218)
Proceeds from financial contracts	26,896	51,716
Securities sold, not yet purchased	268,731	661,061
Dispositions of securities sold, not yet purchased	(595,334)	(726,183)
Change in due to prime brokers and other financial institutions	(152,528)	223,729
Change in notes receivable, net	(115)	107
Net cash provided by (used in) investing activities	(167,099)	113,184
Financing activities
Repurchase of Class A ordinary shares	(2,753)	(2,268)
Net cash provided by (used in) financing activities	(2,753)	(2,268)
Effect of foreign exchange rate changes on cash, cash equivalents and restricted cash	(2,230)	(6,682)
Net increase (decrease) in cash, cash equivalents and restricted cash	(200,716)	151,991
Cash, cash equivalents and restricted cash at beginning of the period (see Note 2)	27,285
Cash, cash equivalents and restricted cash at end of the period (see Note 2)	65,441
Supplementary information
Interest paid in cash	8,123	5,875
Income tax paid in cash	$ 0	$ 0

ORGANIZATION AND BASIS OF PRESE

ORGANIZATION AND BASIS OF PRESENTATION	6 Months Ended
	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION AND BASIS OF PRESENTATION	ORGANIZATION AND BASIS OF PRESENTATION Greenlight Capital Re, Ltd. (“GLRE”) was incorporated as an exempted company under the Companies Law of the Cayman Islands on July 13, 2004. GLRE’s principal wholly-owned subsidiary, Greenlight Reinsurance, Ltd. (“Greenlight Re”), provides global specialty property and casualty reinsurance. Greenlight Re has a Class D insurer license issued in accordance with the terms of The Insurance Law, 2010 and underlying regulations thereto (the “Law”) and is subject to regulation by the Cayman Islands Monetary Authority (“CIMA”), in terms of the Law. Greenlight Re commenced underwriting in April 2006. During 2008, Verdant Holding Company, Ltd. (“Verdant”), a wholly-owned subsidiary of GLRE, was incorporated in the state of Delaware. During 2010, GLRE established Greenlight Reinsurance Ireland, Designated Activity Company (“GRIL”), a wholly-owned reinsurance subsidiary based in Dublin, Ireland. GRIL is authorized as a non-life reinsurance undertaking in accordance with the provisions of the European Union (Insurance and Reinsurance) Regulations 2015 (“Irish Regulations”). GRIL provides multi-line property and casualty reinsurance capacity to the European broker market and provides GLRE with an additional platform to serve clients located in Europe and North America. As used herein, the “Company” refers collectively to GLRE and its consolidated subsidiaries. The Class A ordinary shares of GLRE are listed on Nasdaq Global Select Market under the symbol “GLRE”. These unaudited condensed consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete consolidated financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2017 . In the opinion of management, these unaudited condensed consolidated financial statements reflect all of the normal recurring adjustments considered necessary for a fair presentation of the Company’s financial position and results of operations as of the dates and for the periods presented. The results for the three and six months ended June 30, 2018 are not necessarily indicative of the results expected for the full calendar year. Reclassifications Prior to the year ended December 31, 2017, the Company presented the redeemable and non-redeemable portion of the non-controlling interest in the related party joint venture under the permanent equity section of the balance sheet. The United States Securities and Exchange Commission (“SEC”) guidance, which is applicable to SEC registrants, requires shares, that are not required to be accounted for in accordance with Financial Accounting Standards Board (“FASB”) ASC Topic Distinguishing Liabilities from Equity , and having redemption features that are not solely within the control of the issuer, to be classified outside of the permanent equity section and instead presented in the mezzanine section of the consolidated balance sheets. Effective from the year ended December 31, 2017, the Company presented the redeemable non-controlling interest in the related party joint venture in the mezzanine section on the Company’s consolidated balance sheet in accordance with the SEC guidance noted above. The comparative condensed consolidated statement of shareholders’ equity for the six months ended June 30, 2017 has been reclassified to conform to the current period presentation of the redeemable non-controlling interest in the related party joint venture. The reclassification had no impact on shareholders’ equity attributable to shareholders or retained earnings. In addition, this change did not impact the condensed consolidated statements of income, earnings per share or condensed consolidated statement of cash flows. See Note 8 for additional information regarding the non-controlling interests in the related party joint venture. Additionally, effective from the three and six month periods ended June 30, 2018, contracts that cover more than one line of business are grouped as “multi-line” regardless of whether a portion of the underlying business is covered by one of the lines of business listed above. The prior period comparative information in Note 10 has been reclassified to conform to the current period presentation.

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES Use of Estimates The preparation of 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 and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the period. Actual results could differ from these estimates. Restricted Cash and Cash Equivalents The Company is required to maintain certain cash in segregated accounts with prime brokers and derivative counterparties. The amount of restricted cash held by prime brokers is primarily used to support the liability created from securities sold, not yet purchased and derivatives. Additionally, restricted cash and cash equivalent balances are held to collateralize regulatory trusts and letters of credit issued to cedents (see Notes 4 and 9 ). The amount of cash encumbered varies depending on the market value of the securities sold, not yet purchased, and the collateral required by the cedents in the form of trust accounts and letters of credit. In addition, derivative counterparties require cash collateral to support the current value of any amounts that may be due to the counterparty based on the value of the underlying financial instrument. The following table reconciles the cash, cash equivalents, and restricted cash reported within the condensed consolidated balance sheets to the total presented in the condensed consolidated statements of cash flows: June 30, 2018 December 31, 2017 ($ in thousands) Cash and cash equivalents $ 65,441 $ 27,285 Restricted cash and cash equivalents 1,264,941 1,503,813 Total cash, cash equivalents and restricted cash presented in the condensed consolidated statements of cash flows $ 1,330,382 $ 1,531,098 Premium Revenue Recognition The Company accounts for reinsurance contracts in accordance with U.S. GAAP. In the event that a reinsurance contract does not transfer sufficient risk, deposit accounting is used and the contract is reported as a deposit liability. Similarly for ceded contracts that do not transfer sufficient risk, deposit accounting is used and the contract is reported as a deposit asset. The Company writes excess of loss contracts as well as quota share contracts. The Company estimates the ultimate premiums for the entire contract period. These estimates are based on information received from the ceding companies and estimates from actuarial pricing models used by the Company. For excess of loss contracts, the total ultimate estimated premiums are recorded as premiums written at the inception of the contract. For quota share contracts, the premiums are recorded as written based on cession statements from cedents which typically are received monthly or quarterly depending on the terms specified in each contract. For any reporting lag, premiums written are estimated based on the portion of the ultimate estimated premiums relating to the risks underwritten during the lag period. Premium estimates are reviewed by management at least quarterly. Such review includes a comparison of actual reported premiums to expected ultimate premiums along with a review of the aging and collection of premium estimates. Based on management’s review, the appropriateness of the premium estimates is evaluated, and any adjustments to these estimates are recorded in the period in which they are determined. Changes in premium estimates, including premium receivable on both excess of loss and quota share contracts, are expected and may result in significant adjustments in any period. A significant portion of amounts included in reinsurance balances receivable represent estimated premiums written, net of commissions and brokerage, and are not currently due based on the terms of the underlying contracts. Certain contracts allow for reinstatement premiums in the event of a full limit loss prior to the expiry of a contract. A reinstatement premium is not due until there is a loss event and, therefore, in accordance with U.S. GAAP, the Company records a reinstatement premium as written only in the event that a client incurs a loss on the contract and the contract allows for a reinstatement of coverage upon payment of an additional premium. For catastrophe contracts which contractually require the payment of a reinstatement premium upon the occurrence of a loss, the reinstatement premiums are earned over the original contract period. Reinstatement premiums, that are contractually calculated on a pro-rata basis of the original contract period, are earned over the remaining coverage period. For additional premiums which are due on a contract that has no remaining coverage period, the additional premiums are earned in full when due. Certain contracts may provide for a penalty to be paid if the contract is terminated and canceled prior to its expiration term. Cancellation penalties are recognized in the period the notice of cancellation is received and are recorded in the consolidated statements of income under “other income (expense), net”. Premiums written are generally recognized as earned over the contract period in proportion to the period of risk covered. Unearned premiums consist of the unexpired portion of reinsurance provided. Reinsurance Premiums Ceded The Company reduces the risk of future losses on business assumed by reinsuring certain risks and exposures with other reinsurers (retrocessionaires). The Company remains liable to the extent that any retrocessionaire fails to meet its obligations and to the extent the Company does not hold sufficient security for their unpaid obligations. Ceded premiums are written during the period in which the risks incept and are expensed over the contract period in proportion to the period of protection. Unearned premiums ceded consist of the unexpired portion of reinsurance obtained. Deferred Acquisition Costs Policy acquisition costs, such as commission and brokerage costs, relate directly to, and vary with, the writing of reinsurance contracts. Acquisition costs relating solely to bound contracts are deferred subject to ultimate recoverability and are amortized over the related contract term. The Company evaluates the recoverability of deferred acquisition costs by determining if the sum of future earned premiums and anticipated investment income is greater than the expected future claims and expenses. If a loss is probable on the unexpired portion of policies in force, a premium deficiency loss is recognized. At June 30, 2018 and December 31, 2017 , the deferred acquisition costs were considered fully recoverable and no premium deficiency loss was recorded. Acquisition costs also include profit commissions which are expensed when incurred. Profit commissions are calculated and accrued based on the expected loss experience for contracts and recorded when the current loss estimate indicates that a profit commission is probable under the contract terms. As of June 30, 2018 , $13.9 million ( December 31, 2017 : $11.9 million ) of profit commission reserves were included in reinsurance balances payable on the condensed consolidated balance sheets. For the three and six months ended June 30, 2018 , $3.6 million and $11.6 million , respectively ( 2017 : $3.0 million and $5.7 million , respectively) of net profit commission expense was included in acquisition costs in the condensed consolidated statements of income. Funds Withheld Funds withheld include reinsurance balances retained by the Company on retroceded contracts as collateral in accordance with the contract terms. Any interest expense that the Company incurs while these funds are withheld, is included under net investment income (loss) in the condensed consolidated statements of income. Loss and Loss Adjustment Expense Reserves and Recoverable The Company establishes reserves for contracts based on estimates of the ultimate cost of all losses including losses incurred but not reported (“IBNR”). These estimated ultimate reserves are based on the Company’s own actuarial estimates derived from reports received from ceding companies, industry data and historical experience. These estimates are reviewed by the Company at least quarterly and adjusted as necessary. Since reserves are estimates, the final settlement of losses may vary from the reserves established and any adjustments to the estimates, which may be material, are recorded in the period they are determined. Loss and loss adjustment expenses recoverable include the amounts due from retrocessionaires for unpaid loss and loss adjustment expenses on retrocession agreements. Ceded losses incurred but not reported are estimated based on the Company’s actuarial estimates. These estimates are reviewed periodically and adjusted when deemed necessary. The Company may not be able to ultimately recover the loss and loss adjustment expense recoverable amounts due to the retrocessionaires’ inability to pay. The Company regularly evaluates the financial condition of its retrocessionaires and records provisions for uncollectible reinsurance expenses recoverable when recovery is no longer probable. Consideration paid by the Company for retroactive reinsurance that meets the conditions for reinsurance accounting (e.g. loss portfolio transfers) are reported as loss and loss adjustment expenses recoverable to the extent those amounts do not exceed the associated liabilities. If the amounts paid for retroactive reinsurance exceed the liabilities, the Company increases the related liabilities, at the time the reinsurance contract is effective, and the excess is charged to net income as losses incurred. If the liabilities exceed the amounts paid, the recoverable balance is increased to reflect the difference, and the resulting gain is deferred and amortized over the estimated loss payout period. Changes in the estimated amount of liabilities relating to the underlying reinsured contracts are recognized in net income in the period of the change. Notes Receivable Notes receivable include promissory notes receivable from third party entities. These notes are recorded at cost along with accrued interest, if any, which approximates the fair value. Interest income and realized gains or losses on sale of notes receivable are included under net investment income (loss) in the condensed consolidated statements of income. The Company regularly reviews all notes receivable individually for impairment and records valuation allowance provisions for uncollectible and non-performing notes. The Company places notes on non-accrual status when the recorded value of the note is not considered impaired but there is uncertainty as to the collection of interest in accordance with the terms of the note. For notes receivable placed on non-accrual status, the notes are recorded excluding any accrued interest amount. The Company resumes accrual of interest on a note when none of the principal or interest remains past due, and the Company expects to collect the remaining contractual principal and interest. Interest collected on notes that are placed on non-accrual status is treated on a cash-basis and recorded as interest income when collected, provided that the recorded value of the note is deemed to be fully collectible. Where doubt exists as to the collectability of the remaining recorded value of the notes placed on non-accrual status, any payments received are applied to reduce the recorded value of the notes. At June 30, 2018 , $11.7 million of notes receivable (net of any valuation allowance) were on non-accrual status ( December 31, 2017 : $14.4 million ) and any payments received were applied to reduce the recorded value of the notes. At June 30, 2018 and December 31, 2017 , $0.02 million and $0.1 million , respectively, of accrued interest was included in the notes receivable balance. Based on management’s assessment, the recorded values of the notes receivable, net of valuation allowance, at June 30, 2018 and December 31, 2017 , were expected to be fully collectible. Deposit Assets and Liabilities In accordance with U.S. GAAP, deposit accounting is used in the event that a reinsurance contract does not transfer sufficient insurance risk. The deposit method of accounting requires an asset or liability to be recognized based on the consideration paid or received. The deposit asset or liability balance is subsequently adjusted using the interest method with a corresponding income or expense recorded in the condensed consolidated statements of income as other income or expense. The Company’s deposit assets and liabilities are recorded in the condensed consolidated balance sheets under reinsurance balances receivable and reinsurance balances payable, respectively. At June 30, 2018 , deposit assets and deposit liabilities were $13.2 million and $46.0 million , respectively ( December 31, 2017 : $19.4 million and $28.1 million , respectively). For the three and six months ended June 30, 2018 , interest expense on deposit accounted contracts was $0.4 million and $0.5 million , respectively. For the three and six months ended June 30, 2018 , interest income on deposit accounted contracts was $0.2 million and $0.5 million , respectively. For the three and six months ended June 30, 2017 , there was no material interest expense or interest income on deposit accounted contracts. Financial Instruments Investments in Securities and Investments in Securities Sold, Not Yet Purchased The Company’s investments in debt instruments and equity securities that are classified as “trading securities” are carried at fair value. The fair values of the listed equity investments are derived based on quoted prices (unadjusted) in active markets for identical assets (Level 1 inputs). The fair values of listed equities that have restrictions on sale or transfer which expire within one year, are determined by adjusting the observed market price of the equity using a liquidity discount based on observable market inputs. The fair values of debt instruments are derived based on inputs that are observable, either directly or indirectly, such as market maker or broker quotes reflecting recent transactions (Level 2 inputs), and are generally derived based on the average of multiple market maker or broker quotes which are considered to be binding. Where quotes are not available, debt instruments are valued using cash flow models using assumptions and estimates that may be subjective and non-observable (Level 3 inputs). The Company’s “other investments” may include investments in private and unlisted equity securities, limited partnerships and commodities, which are all carried at fair value. The fair values of commodities are determined based on quoted prices in active markets for identical assets (Level 1). The Company maximizes the use of observable direct or indirect inputs (Level 2 inputs) when deriving the fair values for “other investments”. For limited partnerships and private and unlisted equity securities, where observable inputs are not available, the fair values are derived based on unobservable inputs (Level 3 inputs) such as management’s assumptions developed from available information using the services of the investment advisor, including the most recent net asset values obtained from the managers of those underlying investments. For certain private equity fund investments, the Company has elected to measure the fair value using the net asset value practical expedient allowed under U.S. GAAP, and, accordingly, these investments are not classified as Level 1, 2 or 3 in the fair value hierarchy. For securities classified as “trading securities” and “other investments”, any realized and unrealized gains or losses are determined on the basis of the specific identification method (by reference to cost or amortized cost, as appropriate) and included in net investment income (loss) in the condensed consolidated statements of income. Dividend income and expense are recorded on the ex-dividend date. The ex-dividend date is the date as of when the underlying security must have been traded to be eligible for the dividend declared. Interest income and interest expense are recorded on an accrual basis. Derivative Financial Instruments U.S. GAAP requires that an entity recognize all derivatives in the balance sheet at fair value. It also requires that unrealized gains and losses resulting from changes in fair value be included in income or comprehensive income, depending on whether the instrument qualifies as a hedge transaction, and if so, the type of hedge transaction. The Company’s derivative financial instrument assets are included in financial contracts receivable. Derivative financial instrument liabilities are generally included in financial contracts payable. The Company’s derivatives do not qualify as hedges for financial reporting purposes and are recorded in the condensed consolidated balance sheets on a gross basis and not offset against any collateral pledged or received. Pursuant to the International Swaps and Derivatives Association (“ISDA”) master agreements, securities lending agreements and other agreements, the Company and its counterparties typically have the ability to net certain payments owed to each other in specified circumstances. In addition, in the event a party to one of the ISDA master agreements, securities lending agreements or other agreements defaults, or a transaction is otherwise subject to termination, the non-defaulting party generally has the right to set off outstanding balances due from the defaulting party against payments owed to the defaulting party or collateral held by the non-defaulting party. The Company may, from time to time, enter into underwriting contracts such as industry loss warranty contracts (“ILW”) that are treated as derivatives for U.S GAAP purposes. Financial Contracts The Company enters into financial contracts with counterparties as part of its investment strategy. Financial contracts, which include total return swaps, credit default swaps (“CDS”), futures, options, currency forwards and other derivative instruments, are recorded at their fair value with any unrealized gains and losses included in net investment income (loss) in the condensed consolidated statements of income. Financial contracts receivable represents derivative contracts whereby, based upon the contract’s current fair value, the Company will be entitled to receive payments upon settlement of the contract. Financial contracts payable represents derivative contracts whereby, based upon each contract’s current fair value, the Company will be obligated to make payments upon settlement of the contract. Total return swap agreements, included on the condensed consolidated balance sheets as financial contracts receivable and financial contracts payable, are derivative financial instruments whereby the Company is either entitled to receive or obligated to pay the product of a notional amount multiplied by the movement in an underlying security, which the Company may not own, over a specified time frame. In addition, the Company may also be obligated to pay or receive other payments based on interest rates, dividend payments and receipts, or foreign exchange movements during a specified period. The Company measures its rights or obligations to the counterparty based on the fair value movements of the underlying security together with any other payments due. These contracts are carried at fair value, based on observable inputs (Level 2 inputs) with the resultant unrealized gains and losses reflected in net investment income (loss) in the condensed consolidated statements of income. Additionally, any changes in the value of amounts received or paid on swap contracts are reported as a gain or loss in net investment income (loss) in the condensed consolidated statements of income. Financial contracts may also include exchange traded futures or options contracts that are based on the movement of a particular index, equity security, commodity, currency or interest rate. Where such contracts are traded in an active market, the Company’s obligations or rights on these contracts are recorded at fair value based on the observable quoted prices of the same or similar financial contracts in an active market (Level 1) or on broker quotes which reflect market information based on actual transactions (Level 2). Amounts invested in exchange traded options and over the counter (“OTC”) options are recorded either as an asset or liability at inception. Subsequent to initial recognition, unexpired exchange traded option contracts are recorded at fair value based on quoted prices in active markets (Level 1). For OTC options or exchange traded options where a quoted price in an active market is not available, fair values are derived based upon observable inputs (Level 2) such as multiple quotes from brokers and market makers, which are considered to be binding. The Company may purchase and sell CDS for strategic investment purposes. A CDS is a derivative instrument that provides protection against an investment loss due to specified credit or default events of a reference entity. The seller of a CDS guarantees to pay the buyer a specified amount if the reference entity defaults on its obligations or fails to perform. The buyer of a CDS pays a premium over time to the seller in exchange for obtaining this protection. A CDS trading in an active market is valued at fair value based on broker or market maker quotes for identical instruments in an active market (Level 2) or based on the current credit spreads on identical contracts (Level 2). Share-Based Compensation The Company has established a stock incentive plan for directors, employees and consultants. U.S. GAAP requires the Company to recognize share-based compensation transactions using the fair value at the grant date of the award. The Company measures compensation for restricted shares and restricted stock units (“RSUs”) based on the price of the Company’s common shares at the grant date. For restricted shares and RSUs with both service and performance vesting conditions, the expense is recognized based on management’s estimate of the probability of the performance conditions being achieved based on historical results and expectations of future results. If the performance conditions is expected to be met, the expense is attributed to the period for which the requisite service has been rendered. For restricted shares and RSUs with only service vesting conditions, the expense is recognized on a straight line basis over the vesting period, net of any estimated or expected forfeitures. The forfeiture rate is estimated based on the Company’s historical actual forfeitures relating to restricted shares and RSUs granted to employees. The forfeiture rate is reviewed annually and adjusted as necessary. No forfeiture rate is used for restricted shares granted to directors which vest over a twelve-month period. Determining the fair value of share purchase options at the grant date requires significant estimation and judgment. The Company uses an option-pricing model (Black-Scholes option pricing model) to assist in the calculation of fair value for share purchase options. The model requires estimation of various inputs such as estimated term, forfeiture and dividend rates and expected volatility. In determining the grant date fair value, the Company uses the full life of the options, ten years, as the estimated term of the options, and has assumed no forfeitures and no dividends paid during the life of the options. The estimate of expected volatility is based on the daily historical trading data of the Company’s Class A ordinary shares from the date that these shares commenced trading (May 24, 2007) to the grant date. For share purchase options issued under the employee stock incentive plan, the compensation cost is calculated and expensed over the vesting periods on a graded vesting basis (see Note 7 ). If actual results differ significantly from these estimates and assumptions, particularly in relation to the Company’s estimation of volatility which requires the most judgment, share-based compensation expense, primarily with respect to future share-based awards, could be materially impacted. Foreign Exchange The reporting and functional currency of the Company and all its subsidiaries is the U.S. dollar. Transactions in foreign currencies are recorded in U.S. dollars at the exchange rates in effect on the transaction date. Monetary assets and liabilities in foreign currencies at the balance sheet date are translated at the exchange rate in effect at the balance sheet date and translation exchange gains and losses, if any, are included in “other income (expense), net” in the condensed consolidated statements of income. Comprehensive Income (Loss) The Company has no comprehensive income or loss, other than the net income or loss disclosed in the condensed consolidated statements of income. Earnings (Loss) Per Share Basic earnings per share are based on the weighted average number of common shares and participating securities outstanding during the period. Diluted earnings per share includes the dilutive effect of restricted stock units (“RSU”) and additional potential common shares issuable when stock options are exercised and are determined using the treasury stock method. The Company treats its unvested restricted stock as participating securities in accordance with U.S. GAAP, which requires that unvested stock awards which contain non-forfeitable rights to dividends or dividend equivalents, whether paid or unpaid (referred to as “participating securities”), be included in the number of shares outstanding for both basic and diluted earnings per share calculations. In the event of a net loss, all RSUs, stock options outstanding and participating securities are excluded from the calculation of both basic and diluted loss per share since their inclusion would be anti-dilutive. Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 Weighted average shares outstanding - basic 36,952,472 37,025,703 36,950,828 37,009,539 Effect of dilutive employee and director share-based awards — — — — Weighted average shares outstanding - diluted 36,952,472 37,025,703 36,950,828 37,009,539 Anti-dilutive stock options outstanding 1,015,627 458,741 1,015,627 358,741 Participating securities excluded from calculation of loss per share 462,787 330,102 462,787 330,102 Taxation Under current Cayman Islands law, no corporate entity, including GLRE and Greenlight Re, is obligated to pay taxes in the Cayman Islands on either income or capital gains. The Company has an undertaking from the Governor-in-Cabinet of the Cayman Islands, pursuant to the provisions of the Tax Concessions Law, as amended, that, in the event that the Cayman Islands enacts any legislation that imposes tax on profits, income, gains or appreciations, or any tax in the nature of estate duty or inheritance tax, such tax will not be applicable to GLRE, Greenlight Re nor their respective operations, or to the Class A or Class B ordinary shares or related obligations, until February 1, 2025. Verdant is incorporated in Delaware and, therefore, is subject to taxes in accordance with the U.S. federal rates and regulations prescribed by the U.S. Internal Revenue Service (“IRS”). Verdant’s taxable income is generally expected to be taxed at a marginal rate of 21% . Verdant’s tax years 2014 and beyond, remain open and subject to examination by the IRS. GRIL is incorporated in Ireland and, therefore, is subject to the Irish corporation tax rate of 12.5% on its trading income, and 25% on its non-trading income, if any. Any deferred tax asset is evaluated for recovery and a valuation allowance is recorded when it is more likely than not that the deferred tax asset will not be realized in the future. The Company has not taken any income tax positions that are subject to significant uncertainty or that are reasonably likely to have a material impact on the Company. Recent Accounting Pronouncements In January 2016, the FASB issued ASU 2016-01, “Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”) . The new guidance is intended to improve the recognition and measurement of financial instruments. ASU 2016-01, among other things, requires equity investments to be measured at fair value with changes in fair value recognized in net income or loss, requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes and requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset. ASU 2016-01 affects public and private companies, not-for-profit organizations, and employee benefit plans that hold financial assets or owe financial liabilities. The new guidance is effective for public companies for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted ASU 2016-01 during the first quarter of fiscal year 2018 and the adoption of this guidance did not have any significant impact on the Company’s net income or loss or retained earnings since the Company’s investments are classified as “trading” and the unrealized gains and losses are recognized in net income or loss. The Company has implemented the new disclosures required under ASU 2016-01 commencing from the first quarter of 2018. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”) . Under the new guidance, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. ASU 2016-02 is effective for public companies for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted for any organization in any interim or annual period. The Company currently has operating leases for its office spaces as disclosed in Note 9 of the condensed consolidated financial statements which will be recognized as right-of-use asset upon adoption of ASU 2016-02. The Company is in the process of evaluating the impact of adopting ASU 2016-02 on the Company’s consolidated financial statements and anticipates implementing ASU 2016-02 during the first quarter of fiscal year 2019. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurements of Credit Losses on Financial Instruments” (“ASU 2016-13”) . ASU 2016-13 amends the guidance on reporting credits losses and affects loans, debt securities, trade receivables, reinsurance recoverables and other financial assets that have the contractual right to receive cash. The amendments are effective for annual periods beginning after December 15, 2019, and interim periods within those annual periods. Early adoption is permitted for any organization for annual periods beginning after December 15, 2018 and interim periods within those annual periods. The Company is in the process of evaluating the impact of the requirements of ASU 2016-13 on the Company’s consolidated financial statements and anticipates implementing ASU 2016-13 during the first quarter of fiscal year 2020. In November 2016, the FASB issued ASU 2016-18, “Statements of Cash Flows - Restricted Cash (Topic 230)” (“ASU 2016-18”). ASU 2016-18 requires restricted cash and cash equivalents to be included with cash and cash equivalents in the statement of cash flows and the nature of the restrictions on cash and cash equivalents to be disclosed. ASU 2016-18 is effective for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption was permitted. The Company adopted ASU 2016-18 during the first quarter of fiscal year 2018 and amended the presentation in the statement of cash flows to include the restricted cash and cash equivalents with cash and cash equivalents in the condensed consolidated statements of cash flows and retrospectively reclassified comparative periods presented. The adoption had no impact on the Company’s net income or loss or retained earnings. The FASB has issued ASU No. 2014-09, “Reve

FINANCIAL INSTRUMENTS

FINANCIAL INSTRUMENTS	6 Months Ended
	Jun. 30, 2018
Financial Instruments [Abstract]
FINANCIAL INSTRUMENTS	FINANCIAL INSTRUMENTS In the normal course of its business, the Company purchases and sells various financial instruments, which include listed and unlisted equities, corporate and sovereign debt, commodities, futures, put and call options, currency forwards, other derivatives and similar instruments sold, not yet purchased. Fair Value Hierarchy The Company’s financial instruments are carried at fair value, and the net unrealized gains or losses are included in net investment income (loss) in the condensed consolidated statements of income. The following table presents the Company’s investments, categorized by the level of the fair value hierarchy as of June 30, 2018 : Fair value measurements as of June 30, 2018 Description Quoted prices in Significant other Significant Total ($ in thousands) Assets: Debt instruments $ — $ 12,899 $ 932 $ 13,831 Listed equity securities 809,826 10,667 — 820,493 Commodities 36,225 — — 36,225 Private and unlisted equity securities — — 6,909 6,909 $ 846,051 $ 23,566 $ 7,841 $ 877,458 Unlisted equity funds measured at net asset value (1) 26,117 Total investments $ 903,575 Financial contracts receivable $ 892 $ 67,231 $ — $ 68,123 Liabilities: Listed equity securities, sold not yet purchased $ (570,861 ) $ — $ — $ (570,861 ) Debt instruments, sold not yet purchased — (110,417 ) — (110,417 ) Total securities sold, not yet purchased $ (570,861 ) $ (110,417 ) $ — $ (681,278 ) Financial contracts payable $ (2,504 ) $ (16,242 ) $ — $ (18,746 ) (1) Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets. The following table presents the Company’s investments, categorized by the level of the fair value hierarchy as of December 31, 2017 : Fair value measurements as of December 31, 2017 Description Quoted prices in Significant other Significant Total ($ in thousands) Assets: Debt instruments $ — $ 6,300 $ 880 $ 7,180 Listed equity securities 1,181,150 22,522 — 1,203,672 Commodities 121,502 — — 121,502 Private and unlisted equity securities — — 6,108 6,108 $ 1,302,652 $ 28,822 $ 6,988 $ 1,338,462 Unlisted equity funds measured at net asset value (1) 24,522 Total investments $ 1,362,984 Financial contracts receivable $ 22 $ 12,871 $ — $ 12,893 Liabilities: Listed equity securities, sold not yet purchased $ (812,652 ) $ — $ — $ (812,652 ) Debt instruments, sold not yet purchased — (100,145 ) — (100,145 ) Total securities sold, not yet purchased $ (812,652 ) $ (100,145 ) $ — $ (912,797 ) Financial contracts payable $ — $ (22,222 ) $ — $ (22,222 ) (1) Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets. The following tables present the reconciliation of the balances for all investments measured at fair value using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2018 : Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Three months ended June 30, 2018 Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 885 $ 6,135 $ 7,020 Purchases — 800 800 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 47 (26 ) 21 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 932 $ 6,909 $ 7,841 Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six months ended June 30, 2018 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 880 $ 6,108 $ 6,988 Purchases — 800 800 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 52 1 53 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 932 $ 6,909 $ 7,841 There were no transfers between Level 1, Level 2 or Level 3 during the six months ended June 30, 2018 . The following tables present the reconciliation of the balances for all investments measured at fair value using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2017 : Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Three months ended June 30, 2017 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 704 $ 6,076 $ 6,780 Purchases — — — Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 72 9 81 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 776 $ 6,085 $ 6,861 Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six months ended June 30, 2017 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 654 $ 6,109 $ 6,763 Purchases — 1,750 1,750 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 122 (6 ) 116 Transfers into Level 3 — — — Transfers out of Level 3 — (1,768 ) (1,768 ) Ending balance $ 776 $ 6,085 $ 6,861 During the six months ended June 30, 2017 , $1.8 million of the private equity securities were transferred from Level 3 to Level 2 as these securities commenced trading on a listed exchange. However, due to lock-up period restrictions on those securities, they were classified as Level 2 upon transfer until the lock-up period expires. As of June 30 , 2017 , the fair value of these securities was based on the last traded price on an active market, adjusted for an estimated discount due to the lock-up restriction. There were no other transfers between Level 1, Level 2 or Level 3 during the three and six months ended June 30, 2017 . As of June 30, 2018 , the Company held investments in unlisted equity funds of $26.1 million (December 31, 2017 : $24.5 million ) with fair values measured using the unadjusted net asset values and performance estimates as reported by the managers of these funds as a practical expedient. Some of these net asset values were reported from periods prior to June 30, 2018 . The unlisted equity funds have varying lock-up periods and, as of June 30, 2018 , all of the funds had redemption restrictions. The redemption restrictions have been in place since inception of the investments. One of the unlisted equity funds may be redeemed after December 31, 2018 while the redemption restrictions for the other funds are not expected to lapse in the near future. As of June 30, 2018 , the Company had $6.9 million (December 31, 2017 : $6.5 million ) of unfunded commitments relating to unlisted equity funds whose fair values are determined based on unadjusted net asset values reported by the managers of these funds. These commitments are included in the amounts presented in the schedule of commitments and contingencies in Note 9 of these condensed consolidated financial statements. For the three and six months ended June 30, 2018 and 2017 , there were no net realized gains or losses included in net investment loss in the condensed consolidated statements of income relating to Level 3 securities. For Level 3 securities still held as of the reporting date, the change in net unrealized gains for the three and six months ended June 30, 2018 of $0.02 million and $0.1 million , respectively ( three and six months ended June 30, 2017 : net unrealized gains $0.1 million and $0.1 million , respectively), were included in net investment income (loss) in the condensed consolidated statements of income. Investments Debt instruments, trading At June 30, 2018 , the following investments were included in debt instruments: Cost/amortized cost Unrealized gains Unrealized losses Fair ($ in thousands) Corporate debt – U.S. $ 3,186 $ — $ (2,170 ) $ 1,016 Corporate debt – Non U.S. 2,109 — (2,099 ) 10 Municipal debt – U.S. 7,441 5,364 — 12,805 Total debt instruments $ 12,736 $ 5,364 $ (4,269 ) $ 13,831 At December 31, 2017 , the following investments were included in debt instruments: Cost/amortized cost Unrealized gains Unrealized losses Fair ($ in thousands) Corporate debt – U.S. $ 8,508 $ — $ (7,186 ) $ 1,322 Corporate debt – Non U.S. 2,109 — (2,057 ) 52 Municipal debt – U.S. 5,831 — (25 ) 5,806 Total debt instruments $ 16,448 $ — $ (9,268 ) $ 7,180 The maturity distribution for debt instruments held at June 30, 2018 and December 31, 2017 was as follows: June 30, 2018 December 31, 2017 Cost/ Fair Cost/ Fair ($ in thousands) Within one year $ 1,551 $ 234 $ 7,557 $ 441 From one to five years 892 217 — — From five to ten years 2,859 1,324 2,109 52 More than ten years 7,434 12,056 6,782 6,687 $ 12,736 $ 13,831 $ 16,448 $ 7,180 Equity securities, trading At June 30, 2018 , the following long positions were included in equity securities, trading: Cost Unrealized Unrealized Fair ($ in thousands) Equities – listed $ 754,110 $ 121,165 $ (54,782 ) $ 820,493 Total equity securities $ 754,110 $ 121,165 $ (54,782 ) $ 820,493 At December 31, 2017 , the following long positions were included in equity securities, trading: Cost Unrealized Unrealized Fair ($ in thousands) Equities – listed $ 1,014,426 $ 208,350 $ (19,104 ) $ 1,203,672 Total equity securities $ 1,014,426 $ 208,350 $ (19,104 ) $ 1,203,672 Other Investments “Other investments” include commodities and private securities and unlisted funds. As of June 30, 2018 and December 31, 2017 , all commodities were comprised of gold bullion. At June 30, 2018 , the following securities were included in other investments: Cost Unrealized Unrealized Fair ($ in thousands) Commodities $ 29,493 $ 6,732 $ — $ 36,225 Private and unlisted equity funds 25,803 7,223 — 33,026 $ 55,296 $ 13,955 $ — $ 69,251 At December 31, 2017 , the following securities were included in other investments: Cost Unrealized Unrealized Fair ($ in thousands) Commodities $ 101,184 $ 20,318 $ — $ 121,502 Private and unlisted equity funds 25,316 5,314 — 30,630 $ 126,500 $ 25,632 $ — $ 152,132 Private and unlisted equity funds include private equity securities that did not have readily determinable fair values. At June 30, 2018 the carrying value of the private equity securities was $4.0 million (December 31, 2017 : $3.9 million). The carrying values of the private equity securities are determined based on the original cost and any subsequent changes in the valuation based on periodic third party valuations or recent observable transactions of those securities. There were no meaningful upward or downward adjustments to the carrying values of the private equity securities for the three and six months ended June 30, 2018 . Investments in Securities Sold, Not Yet Purchased Securities sold, not yet purchased, are securities that the Company has sold, but does not own, in anticipation of a decline in the market value of the security. The Company’s risk is that the value of the security will increase rather than decline. Consequently, the settlement amount of the liability for securities sold, not yet purchased, may exceed the amount recorded in the condensed consolidated balance sheet as the Company is obligated to purchase the securities sold, not yet purchased, in the market at prevailing prices to settle its obligations. To establish a position in a security sold, not yet purchased, the Company needs to borrow the security for delivery to the buyer. On each day the transaction is open, the liability for the obligation to replace the borrowed security is marked-to-market and an unrealized gain or loss is recorded. At the time the transaction is closed, the Company realizes a gain or loss equal to the difference between the price at which the security was sold and the cost of replacing the borrowed security. While the transaction is open, the Company will also incur an expense for any dividends or interest which will be paid to the lender of the securities. At June 30, 2018 , the following securities were included in investments in securities sold, not yet purchased: Proceeds Unrealized gains Unrealized losses Fair value ($ in thousands) Corporate debt – U.S. $ (8,779 ) $ — $ (279 ) $ (9,058 ) Equities – listed (456,038 ) 6,163 (120,987 ) (570,862 ) Sovereign debt – Non U.S. (96,230 ) — (5,128 ) (101,358 ) $ (561,047 ) $ 6,163 $ (126,394 ) $ (681,278 ) At December 31, 2017 , the following securities were included in investments in securities sold, not yet purchased: Proceeds Unrealized gains Unrealized losses Fair value ($ in thousands) Equities – listed $ (643,148 ) $ 17,541 $ (187,045 ) $ (812,652 ) Sovereign debt – Non U.S. (96,231 ) — (3,914 ) (100,145 ) $ (739,379 ) $ 17,541 $ (190,959 ) $ (912,797 ) Financial Contracts As of June 30, 2018 and December 31, 2017 , the Company had entered into total return equity swaps, interest rate swaps, commodity swaps, options, warrants, rights, futures and forward contracts with various financial institutions to meet certain investment objectives. Under the terms of each of these financial contracts, the Company is either entitled to receive or is obligated to make payments, which are based on the product of a formula contained within each contract that includes the change in the fair value of the underlying or reference security. At June 30, 2018 , the fair values of financial contracts outstanding were as follows: Financial Contracts Listing (1) Notional amount of Fair value of net assets ($ in thousands) Financial contracts receivable Commodity Swaps USD 33,924 $ 1,575 Futures USD 45,588 892 Interest rate options USD 1,783,000 1,296 Interest rate swaps JPY 21,652 93 Put options USD 126,059 52,946 Total return swaps – equities EUR/GBP/KRW/USD 93,762 11,321 Total financial contracts receivable, at fair value $ 68,123 Financial contracts payable Forwards KRW 56,810 $ (1,775 ) Futures USD 69,839 (2,504 ) Put options USD 24,565 (13,014 ) Total return swaps – equities EUR/RON 17,207 (1,453 ) Total financial contracts payable, at fair value $ (18,746 ) (1) USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu. At December 31, 2017 , the fair values of financial contracts outstanding were as follows: Financial Contracts Listing currency (1) Notional amount of Fair value of net assets ($ in thousands) Financial contracts receivable Call options USD 2,656 $ 91 Commodity Swaps USD 17,833 2,142 Forwards KRW 41,379 801 Futures USD 5,874 12 Interest rate swaps JPY 21,269 479 Put options (2) USD 155 1 Total return swaps – equities EUR/GBP/USD 34,965 9,357 Warrants and rights on listed equities EUR/USD 29 10 Total financial contracts receivable, at fair value $ 12,893 Financial contracts payable Commodity Swaps USD 26,795 $ (353 ) Put options USD 130 (14 ) Total return swaps – equities EUR/GBP/KRW/RON/USD 60,663 (21,855 ) Total financial contracts payable, at fair value $ (22,222 ) (1) USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu. (2) Includes options on the Chinese Yuan, denominated in U.S. dollars. Options are derivative financial instruments that give the buyer, in exchange for a premium payment, the right, but not the obligation, to either purchase from (call option) or sell to (put option) the writer, a specified underlying security at a specified price on or before a specified date. The Company enters into option contracts to meet certain investment objectives. For exchange traded option contracts, the exchange acts as the counterparty to specific transactions and therefore bears the risk of delivery to and from counterparties of specific positions. As of June 30, 2018 , the Company held $52.9 million OTC put options (long) ( December 31, 2017 : nil ) and $13.0 million OTC put options (short) ( December 31, 2017 : nil ). During the three and six months ended June 30, 2018 and 2017 , the Company reported gains and losses on derivatives as follows: Derivatives not designated as hedging instruments Location of gains and losses on derivatives recognized in income Gain (loss) on derivatives recognized in income Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) Forwards Net investment income (loss) $ (2,784 ) $ (289 ) $ (2,907 ) $ 334 Futures Net investment income (loss) (6,003 ) 110 (7,952 ) (403 ) Interest rate options Net investment income (loss) (517 ) — (1,154 ) — Interest rate swaps Net investment income (loss) (118 ) (198 ) (449 ) (93 ) Options, warrants, and rights Net investment income (loss) (14,929 ) (4,584 ) (13,842 ) (12,112 ) Commodity swaps Net investment income (loss) 2,308 (3,746 ) 4,156 (10,705 ) Total return swaps – equities Net investment income (loss) 9,793 (10,593 ) (9,238 ) (282 ) Total $ (12,250 ) $ (19,300 ) $ (31,386 ) $ (23,261 ) The Company generally does not enter into derivatives for risk management or hedging purposes. The volume of derivative activities varies from period to period depending on potential investment opportunities. For the three and six months ended June 30, 2018 , the Company’s volume of derivative activities (based on notional amounts) was as follows: 2018 Three months ended June 30 Six months ended June 30 Derivatives not designated as hedging instruments (notional amounts) Entered Exited Entered Exited ($ in thousands) Forwards $ 9,156 $ 14,438 $ 63,528 $ 47,766 Futures 110,201 76,814 423,374 312,712 Interest rate options (1) 679,000 — 1,783,000 — Options, warrants and rights (1) 73,406 9,280 245,986 26,646 Commodity swaps 34,792 20,948 34,792 49,923 Total return swaps 8,256 13,161 16,850 32,139 Total $ 914,811 $ 134,641 $ 2,567,530 $ 469,186 (1) Exited amount excludes derivatives which expired or were exercised during the period. For the three and six months ended June 30, 2017 , the Company’s volume of derivative activities (based on notional amounts) was as follows: 2017 Three months ended June 30 Six months ended June 30 Derivatives not designated as hedging instruments (notional amounts) Entered Exited Entered Exited ($ in thousands) Forwards $ 164 $ — $ 3,640 $ — Futures 2,890 5,818 32,400 29,887 Options, warrants and rights (1) 229,999 — 577,917 110,102 Commodity swaps 2,025 8,406 2,025 16,588 Total return swaps 11,377 235,806 243,495 296,413 Total $ 246,455 $ 250,030 $ 859,477 $ 452,990 (1) Exited amount excludes derivatives which expired or were exercised during the period. The Company does not offset its derivative instruments and presents all amounts in the condensed consolidated balance sheets on a gross basis. The Company has pledged cash collateral to derivative counterparties to support the current value of amounts due to the counterparties on its derivative instruments. As of June 30, 2018 , the gross and net amounts of derivative instruments and the cash collateral applicable to derivative instruments were as follows: June 30, 2018 (i) (ii) (iii) = (i) - (ii) (iv) Gross amounts not offset in the balance sheet (v) = (iii) + (iv) Description Gross amounts of recognized assets (liabilities) Gross amounts offset in the balance sheet Net amounts of assets (liabilities) presented in the balance sheet Financial instruments available for offset Cash collateral (received) pledged Net amount of asset (liability) ($ in thousands) Financial contracts receivable $ 68,123 $ — $ 68,123 $ (15,359 ) $ (22,933 ) $ 29,831 Financial contracts payable (18,746 ) — (18,746 ) 15,359 — (3,387 ) As of December 31, 2017 , the gross and net amounts of derivative instruments and the cash collateral applicable to derivative instruments were as follows: December 31, 2017 (i) (ii) (iii) = (i) - (ii) (iv) Gross amounts not offset in the balance sheet (v) = (iii) + (iv) Description Gross amounts of recognized assets (liabilities) Gross amounts offset in the balance sheet Net amounts of assets (liabilities) presented in the balance sheet Financial instruments available for offset Cash collateral (received) pledged Net amount of asset (liability) ($ in thousands) Financial contracts receivable $ 12,893 $ — $ 12,893 $ (5,128 ) $ (1,336 ) $ 6,429 Financial contracts payable (22,222 ) — (22,222 ) 5,128 17,094 —

DUE TO PRIME BROKERS

DUE TO PRIME BROKERS	6 Months Ended
	Jun. 30, 2018
Due to and from Broker-Dealers and Clearing Organizations [Abstract]
DUE TO PRIME BROKERS	DUE TO PRIME BROKERS AND OTHER FINANCIAL INSTITUTIONS As of June 30, 2018 , the amount due to prime brokers is comprised of margin-borrowing from prime brokers and custodians relating to investments purchased on margin as well as margin-borrowing for providing collateral to support some of the Company’s outstanding letters of credit and trust accounts (see Note 9 ). Under term margin agreements with prime brokers and revolving credit facilities with custodians and a letter of credit facility agreement, the Company pledges certain investment securities to borrow cash. The cash borrowed under letter of credit facility agreement is placed in a custodial account in the name of the Company and this custodial account provides collateral for any letters of credit issued. Similarly for the trust accounts, the Company may borrow cash from prime brokers or custodians which is placed in a trust account for the benefit of the cedent. Since there is no legal right of offset, the Company’s liability for the cash borrowed from the prime brokers and custodians is included on the condensed consolidated balance sheets as due to prime brokers and other financial institutions while the cash held in the custodial account and trust accounts are included on the condensed consolidated balance sheets as restricted cash and cash equivalents. June 30, 2018 December 31, 2017 ($ in thousands) Due to Prime Brokers $ 490,172 $ 647,700 Due to Other Financial Institutions 30,000 25,000 $ 520,172 $ 672,700 Greenlight Re’s investment guidelines, among other stipulations in the guidelines, allow for up to 15% (GRIL: 5% ) net margin leverage for extended periods of time and up to 30% (GRIL: 20% ) net margin leverage relating to investing activities for periods of less than 30 days.

LOSS AND LOSS ADJUSTMENT EXPENS

LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES (Notes)	6 Months Ended
	Jun. 30, 2018
Insurance Loss Reserves [Abstract]
Liability for Future Policy Benefits and Unpaid Claims Disclosure [Text Block]	LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES There were no significant changes in the actuarial methodology or assumptions relating to the Company’s loss and loss adjustment expense reserves for the six months ended June 30, 2018 . At June 30, 2018 and December 31, 2017 , loss and loss adjustment expense reserves were comprised of the following: Consolidated June 30, 2018 December 31, 2017 ($ in thousands) Case reserves $ 170,389 $ 178,088 IBNR 303,949 286,292 Total $ 474,338 $ 464,380 At June 30, 2018 and December 31, 2017 , the loss and loss adjustment expense reserves relating to health were $24.7 million and $22.2 million , respectively. A summary of changes in outstanding loss and loss adjustment expense reserves for the six months ended June 30, 2018 and 2017 is as follows: Consolidated 2018 2017 ($ in thousands) Gross balance at January 1 $ 464,380 $ 306,641 Less: Losses recoverable (29,459 ) (2,704 ) Net balance at January 1 434,921 303,937 Incurred losses related to: Current year 184,102 203,922 Prior years (3,463 ) 6,906 Total incurred 180,639 210,828 Paid losses related to: Current year (55,909 ) (60,134 ) Prior years (121,609 ) (99,763 ) Total paid (177,518 ) (159,897 ) Foreign currency revaluation (709 ) 1,826 Net balance at June 30 437,333 356,694 Add: Losses recoverable 37,005 2,661 Gross balance at June 30 $ 474,338 $ 359,355 The changes in the outstanding loss and loss adjustment expense reserves for health claims for the six months ended June 30, 2018 and 2017 are as follows: Health 2018 2017 ($ in thousands) Gross balance at January 1 $ 22,181 $ 18,993 Less: Losses recoverable — — Net balance at January 1 22,181 18,993 Incurred losses related to: Current year 27,046 21,674 Prior years 765 (384 ) Total incurred 27,811 21,290 Paid losses related to: Current year (8,740 ) (7,704 ) Prior years (16,564 ) (14,637 ) Total paid (25,304 ) (22,341 ) Foreign currency revaluation — — Net balance at June 30 24,688 17,942 Add: Losses recoverable — — Gross balance at June 30 $ 24,688 $ 17,942 For the six months ended June 30, 2018 , the net losses incurred relating to prior accident years decreased by $3.5 million , which primarily related to the following: • $5.8 million of favorable loss development, net of retrocession recoveries, relating to 2017 hurricanes resulting from updated reporting received from cedents; • $3.5 million of favorable loss development on prior period mortgage insurance contracts resulting from continued favorable claims experience; • $3.5 million of favorable prior period experience on property contracts stemming from accident years 2015 and 2016 where claims experience has been better than expected; • $3.4 million of adverse loss development on non-standard automobile contracts stemming from the difficult market conditions faced by the industry during 2015; • $3.2 million of adverse loss development on solicitors professional indemnity contracts resulting from adverse reporting of claims in excess of expected claims; • $1.9 million of adverse loss development on general liabilities contracts across two accounts, spread over treaty years 2012-2017, resulting from deteriorations in claims experience; • $1.2 million of adverse loss development on surety contracts, net of retrocession recoveries, due to deteriorations in circumstances on several previously reported claims for a single legacy contract; and • The remaining $0.4 million of favorable loss development was due to development across various other multi-line, casualty and other contracts. For the six months ended June 30, 2017 , the net loss reserves on prior period contracts increased by $6.9 million , primarily related to the adverse loss development on Florida homeowners’ insurance contracts relating to the practice of “assignment of benefits”, large claims reported on a surety contract and adverse development on a legacy motor liability contract. There were no other significant developments of prior period reserves during the six months ended June 30, 2017 .

RETROCESSION

RETROCESSION	6 Months Ended
	Jun. 30, 2018
Reinsurance Disclosures [Abstract]
RETROCESSION	RETROCESSION The Company, from time to time, purchases retrocessional coverage for one or more of the following reasons: to manage its overall exposure, to reduce its net liability on individual risks, to obtain additional underwriting capacity and to balance its underwriting portfolio. Additionally, retrocession can be used as a mechanism to share the risks and rewards of business written and, therefore, can be used as a tool to align the Company’s interests with those of its counterparties. The Company currently has coverage that provides for recovery of a portion of loss and loss expenses incurred on certain contracts. Loss and loss adjustment expense recoverable from the retrocessionaires are recorded as assets. For the three and six months ended June 30, 2018 , loss and loss adjustment expenses incurred of $84.8 million and $180.6 million , respectively ( 2017 : $106.0 million and $210.8 million , respectively), reported on the condensed consolidated statements of income are net of loss and loss expenses recovered and recoverable of $15.3 million and $34.7 million , respectively ( 2017 : $(0.2) million and $(0.1) million , respectively). Retrocession contracts do not relieve the Company from its obligations to the insureds. Failure of retrocessionaires to honor their obligations could result in losses to the Company. At June 30, 2018 , the Company had losses receivable and loss reserves recoverable of $31.0 million ( December 31, 2017 : $26.3 million ) from unrated retrocessionaires which were secured by cash and collateral held in trust accounts for the benefit of the Company. At June 30, 2018 , $6.0 million ( December 31, 2017 : $3.1 million ) of losses recoverable were from retrocessionaires rated A- or above by A.M. Best. The Company regularly evaluates the financial condition of its retrocessionaires to assess the ability of the retrocessionaires to honor their respective obligations. At June 30, 2018 and December 31, 2017 , no provision for uncollectible losses recoverable was considered necessary.

SHARE-BASED COMPENSATION

SHARE-BASED COMPENSATION	6 Months Ended
	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
SHARE-BASED COMPENSATION	SHARE-BASED COMPENSATION The Company has a stock incentive plan for directors, employees and consultants that is administered by the Compensation Committee of the Board of Directors. The Company’s shares authorized for issuance pursuant to the stock incentive plan include 5,000,000 ( December 31, 2017 : 5,000,000 ) Class A ordinary shares. As of June 30, 2018 , 1,011,840 ( December 31, 2017 : 1,271,154 ) Class A ordinary shares remained available for future issuance under the Company’s stock incentive plan. Employee and Director Restricted Shares As part of its stock incentive plan, the Company issues restricted shares for which the fair value is equal to the price of the Company’s Class A ordinary shares on the grant date. Compensation based on the grant date fair market value of the shares is expensed on a straight line basis over the applicable vesting period, net of any estimated forfeitures. For the six months ended June 30, 2018 , 191,255 ( 2017 : 113,955 ) Class A ordinary shares were issued to employees pursuant to the Company’s stock incentive plan. The majority of these shares contain certain restrictions relating to, among other things, vesting, forfeiture in the event of termination of employment and transferability. The restricted shares cliff vest after three years from the date of issuance, subject to the grantee’s continued service with the Company. During the vesting period, the holder of the restricted shares retains voting rights and is entitled to any dividends declared by the Company. For the six months ended June 30, 2018 , 30,660 of the restricted shares granted contained service and performance conditions. These restricted shares will cliff vest 5.5 years from the date of issuance, subject to the satisfaction of both the service and performance conditions. For the six months ended June 30, 2018 , the Company also issued to non-employee directors an aggregate of 54,720 ( 2017 : 37,840 ) restricted Class A ordinary shares as part of their remuneration for services to the Company. Each of these restricted shares issued to non-employee directors contains similar restrictions to those issued to employees and will vest on the earlier of the first anniversary of the date of the share issuance or the Company’s next annual general meeting, subject to the grantee’s continued service with the Company. For the six months ended June 30, 2018 , 14,314 ( 2017 : 46,319 ) restricted shares were forfeited by employees who left the Company prior to the expiration of the applicable vesting periods. For the six months ended June 30, 2018 , in accordance with U.S. GAAP, $0.1 million stock compensation expense ( 2017 : nil ) relating to the forfeited restricted shares was reversed. The restricted shares forfeited during the comparative six month period ended June 30, 2017 related to the Company’s former Chief Executive Officer (the “former CEO”) who resigned from the Company prior to the expiration of the applicable vesting periods. For the six months ended June 30, 2017, no stock compensation expense was reversed relating to the former CEO’s forfeited shares since the stock compensation relating to those restricted shares was reversed during the fourth quarter of 2016, when it was deemed likely that these restricted shares would be forfeited. The following table summarizes the activity for unvested outstanding restricted share awards during the six months ended June 30, 2018 : Number of Weighted Balance at December 31, 2017 331,510 $ 23.45 Granted 245,975 15.78 Vested (100,384 ) 27.74 Forfeited (14,314 ) 21.61 Balance at June 30, 2018 462,787 $ 18.50 Employee and Director Stock Options For the six months ended June 30, 2018 and 2017, no Class A ordinary share purchase options were granted. For the six months ended June 30, 2018 and 2017, no stock options were exercised by directors or employees resulting in no Class A ordinary shares issued. When stock options are granted, the Company reduces the corresponding number from the shares authorized for issuance as part of the Company’s stock incentive plan. For the six months ended June 30, 2018 , no stock options vested. For the three and six months ended June 30, 2017 , 71,335 stock options vested, relating to the resignation of the former CEO, which had a weighted average grant date fair value of $10.51 per share, pursuant to the former CEO’s deed of settlement and release. At June 30 , 2017 there was no remaining compensation cost to be recognized in future periods relating to the former CEO’s stock options as the expense was recognized in full as of December 31, 2016 when it was deemed likely that the stock options would vest. Employee and director stock option activity during the six months ended June 30, 2018 was as follows: Number of Weighted Weighted Intrinsic value ($ in millions) Weighted average remaining contractual term Balance at December 31, 2017 1,015,627 $ 23.55 $ 9.89 $ — 6.9 years Granted — — — Exercised — — — Forfeited — — — Expired — — — Balance at June 30, 2018 1,015,627 $ 23.55 $ 9.89 $ — 6.4 years Employee Restricted Stock Units The Company issues restricted stock units (“RSUs”) to certain employees as part of the stock incentive plan. The grant date fair value of the RSUs is equal to the price of the Company’s Class A ordinary shares on the grant date. Compensation cost based on the grant date fair market value of the RSUs is expensed on a straight line basis over the vesting period. For the six months ended June 30, 2018 , 28,301 ( 2017 : 11,559 ) RSUs were issued to employees pursuant to the Company’s stock incentive plan. These shares contain certain restrictions relating to, among other things, vesting, forfeiture in the event of termination of employment and transferability. Each of these RSUs cliff vest after three years from the date of issuance, subject to the grantee’s continued service with the Company. On the vesting date, the Company converts each RSU into one Class A ordinary share and issues new Class A ordinary shares from the shares authorized for issuance as part of the Company’s stock incentive plan. For the six months ended June 30, 2018 , 648 ( 2017 : nil ) RSUs were forfeited by employees, resulting in an immaterial reversal ( 2017 : nil ) of stock compensation expense. Employee RSU activity during the six months ended June 30, 2018 was as follows: Number of Weighted Balance at December 31, 2017 22,798 $ 23.50 Granted 28,301 15.90 Vested (4,053 ) 32.21 Forfeited (648 ) 21.65 Balance at June 30, 2018 46,398 $ 18.13 For the six months ended June 30, 2018 and 2017 , the general and administrative expenses included stock compensation expense (net of forfeitures) of $2.5 million and $1.9 million , respectively, for the expensing of the fair value of stock options, restricted stock and RSUs granted to employees and directors, net of forfeitures.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	6 Months Ended
	Jun. 30, 2018
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS Investment Advisory Agreement The Company and its reinsurance subsidiaries are party to a joint venture agreement with DME Advisors, LP (“DME Advisors”) under which the Company, its reinsurance subsidiaries and DME Advisors LLC (“DME”) are participants of a joint venture for the purpose of managing certain jointly held assets, (“Joint Venture”) as may be amended from time to time (the “venture agreement”). In addition, the Company, its reinsurance subsidiaries and DME have entered into a separate investment advisory agreement with DME Advisors, as may be amended from time to time (the “advisory agreement”). Effective January 1, 2017, the venture agreement and the advisory agreements were amended and restated to replace the previous agreements dated January 1, 2014, and will expire on December 31, 2019 and renew automatically for successive three-year periods. DME and DME Advisors are related to the Company and each is an affiliate of David Einhorn, Chairman of the Company’s Board of Directors. Pursuant to the venture agreement, performance allocation equal to 20% of the net investment income of the Company’s share of the account managed by DME Advisors is allocated, subject to a loss carry forward provision, to DME’s account. The loss carry forward provision requires DME to earn a reduced performance allocation of 10% on net investment income in any year subsequent to the year in which the investment account incurs a loss, until all the losses are recouped and an additional amount equal to 150% of the aggregate investment loss is earned. DME is not entitled to earn a performance allocation in a year in which the investment portfolio incurs a loss. For the three and six months ended June 30, 2018 , no performance allocation was deducted due to the investment loss ( 2017 : reversal of $1.2 million and nil , respectively). Pursuant to the advisory agreement, a monthly management fee, equal to 0.125% ( 1.5% on an annual basis) of the Company’s investment account managed by DME Advisors, is paid to DME Advisors. Included in the net investment income (loss) for the three and six months ended June 30, 2018 were management fees of $4.1 million and $8.6 million , respectively ( 2017 : $4.3 million and $8.6 million , respectively). The management fees have been fully paid as of June 30, 2018 . Pursuant to the venture and advisory agreements, the Company has agreed to indemnify DME and DME Advisors for any expense, loss, liability, or damage arising out of any claim asserted or threatened in connection with DME Advisors serving as the Company’s investment advisor. The Company will reimburse DME and DME Advisors for reasonable costs and expenses of investigating and/or defending such claims, provided such claims were not caused due to gross negligence, breach of contract or misrepresentation by DME or DME Advisors. For the six months ended June 30, 2018 , there were no indemnification payments payable or paid by the Company. Non-controlling Interest in Related Party Joint Venture Non-controlling interests in related party joint venture represents DME’s share of the jointly held assets under the venture agreement. The joint venture created through the venture agreement has been consolidated in accordance with ASC 810, Consolidation (ASC 810). The Company has recorded DME’s minority interests as redeemable non-controlling interests in related party and non-controlling interests in related party in the condensed consolidated balance sheets. A portion of the non-controlling interest is subject to contractual withdrawal rights whereby DME, at its sole discretion, can withdraw its interest above the minimum capital required to be maintained in its capital accounts. This additional capital is therefore recorded on the Company’s condensed consolidated balance sheets within the mezzanine section as redeemable non-controlling interest in related party joint venture whereas the required minimum capital is recorded as non-controlling interests in related party joint venture within the equity section on the Company’s condensed consolidated balance sheet since it does not have withdrawal rights. The following table is a reconciliation of the beginning and ending carrying amounts of redeemable non-controlling interests in related party, non-controlling interests in related party and total non-controlling interests in related party for the six months ended June 30, 2018 and 2017 (see Note 1 for additional information on changes in the presentation of non-controlling interests): Redeemable non-controlling interest in related party joint venture Non-controlling interest in related party joint venture Total non-controlling interest in related party joint venture Six months ended June 30 Six months ended June 30 Six months ended June 30 2018 2017 2018 2017 2018 2017 Opening balance $ 7,169 $ 5,884 — $ 12,933 $ 11,561 — $ 20,102 $ 17,445 Income (loss) attributed to non-controlling interest (1,079 ) (97 ) — (1,868 ) (201 ) — (2,947 ) (298 ) Net contribution into (withdrawal from) non-controlling interest 346 (420 ) — (346 ) 420 — — — Ending balance $ 6,436 $ 5,367 $ 10,719 $ 11,780 $ 17,155 $ 17,147 Green Brick Partners, Inc. David Einhorn also serves as the Chairman of the Board of Directors of Green Brick Partners, Inc. (“GRBK”), a publicly traded company. As of June 30, 2018 , $34.0 million ( December 31, 2017 : $39.2 million ) of GRBK listed equities were included on the balance sheet as “equity securities, trading, at fair value”. The Company, along with certain affiliates of DME Advisors, collectively own 49% of the issued and outstanding common shares of GRBK. Under applicable securities laws, DME Advisors may be limited at times in its ability to trade GRBK shares on behalf of the Company. Service Agreement The Company has entered into a service agreement with DME Advisors, pursuant to which DME Advisors provides certain investor relations services to the Company for compensation of five thousand dollars per month (plus expenses). The agreement is automatically renewed annually until terminated by either the Company or DME Advisors for any reason with 30 days prior written notice to the other party.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Letters of Credit and Trusts At June 30, 2018 , the Company had the following letter of credit facilities, which automatically renew each year unless terminated by either party in accordance with the applicable required notice period: Facility Termination Date Notice period required for termination ($ in thousands) Butterfield Bank (Cayman) Limited $ 50,000 June 30, 2019 90 days prior to termination date Citibank Europe plc 400,000 October 11, 2019 120 days prior to termination date $ 450,000 On March 28, 2018, the Butterfield Bank facility was decreased from $100.0 million to $50.0 million . As of June 30, 2018 , an aggregate amount of $192.5 million ( December 31, 2017 : $188.5 million ) in letters of credit were issued under the above facilities. Under the facilities, the Company provides collateral that may consist of equity securities, restricted cash, and cash and cash equivalents. As of June 30, 2018 , total equity securities, restricted cash, and cash and cash equivalents with a fair value in the aggregate of $198.7 million ( December 31, 2017 : $200.4 million ) were pledged as collateral against the letters of credit issued (also see Note 4 ). Each of the facilities contain customary events of default and restrictive covenants, including but not limited to, limitations on liens on collateral, transactions with affiliates, mergers and sales of assets, as well as solvency and maintenance of certain minimum pledged equity requirements, and restricts issuance of any debt without the consent of the letter of credit provider. Additionally, if an event of default exists, as defined in the letter of credit facilities, Greenlight Re will be prohibited from paying dividends to its parent company. The Company was in compliance with all the covenants of each of these facilities as of June 30, 2018 and December 31, 2017 . In addition to the letters of credit, the Company has established regulatory trust arrangements for certain cedents. As of June 30, 2018 , collateral of $380.9 million ( December 31, 2017 : $377.9 million ) was provided to cedents in the form of regulatory trust accounts. Revolving Credit Facility The Joint Venture has entered into a secured revolving credit facility with The Bank of Nova Scotia (the “credit facility”), to provide funding for its investment activities. At June 30, 2018 , the Joint Venture had the ability to borrow $50.0 million (the “commitment”) under the credit facility and had borrowed $30.0 million ( December 31, 2017 : $25.0 million ). At June 30, 2018 , the interest rate on the credit facility was 3.11% ( December 31, 2017 : 2.47% ) and the Joint Venture and certain of the Company’s subsidiaries, solely as “Participants” in the Joint Venture under the venture agreement, had pledged $36.2 million ( December 31, 2017 : $37.7 million ) of their physical gold holdings as collateral against the borrowed funds. For the six months ended June 30, 2018 , interest expense pursuant to the credit facility was $0.4 million ( 2017 : nil ) and was included in net investment loss in the condensed consolidated statements of income. The credit facility matures on November 8, 2018 and can be extended for one year by the Joint Venture upon providing 120 days’ notice to the lender. Subsequent to June 30, 2018 , the Joint Venture provided notice to extend the credit facility for one additional year. The Joint Venture may terminate or reduce the commitment by giving 10 business days’ notice prior to the effective date of termination or reduction and prepaying the applicable principal obligation and all interest accrued thereon. The credit facility contains certain events of default and restrictive covenants, including but not limited to, limitations on liens on the pledged collateral, mergers and sales of assets and limitations on distributions. The Joint Venture was in compliance with all the covenants of this facility as of June 30, 2018 . Operating Lease Obligations Greenlight Re has entered into lease agreements for office space in the Cayman Islands. Under the terms of the lease agreements, Greenlight Re is committed to annual rent payments ranging from $0.3 million at inception to $0.5 million at lease termination. The leases expired on June 30, 2018 and Greenlight Re has the option to renew the leases for a further five -year term. The Company is in negotiations with the lessor for renewal of the lease and meanwhile has agreed to a monthly lease until December 31, 2018. GRIL has entered into a lease agreement for office space in Dublin, Ireland. Under the terms of this lease agreement, GRIL is committed to minimum annual rent payments denominated in Euros approximating €0.1 million until May 2021, and adjusted to the prevailing market rates for each of the two subsequent five-year terms. GRIL has the option to terminate the lease agreement in 2021. Included in the schedule below are the net minimum lease payment obligations relating to this lease as of June 30, 2018 . The total rent expense related to leased office space for the three and six months ended June 30, 2018 was $0.2 million and $0.3 million , respectively ( 2017 : $0.2 million and $0.3 million , respectively). Private Equity and Limited Partnerships From time to time, the Company makes investments in private equity vehicles. As part of the Company’s participation in such private equity investments, the Company may make funding commitments. As of June 30, 2018 , the Company had commitments to invest an additional $7.0 million ( December 31, 2017 : $6.5 million ) in private equity investments. Included in the schedule below are the minimum payment obligations relating to these investments as of June 30, 2018 . Schedule of Commitments and Contingencies The following is a schedule of future minimum payments required under the above commitments: 2018 2019 2020 2021 2022 Thereafter Total ($ in thousands) Operating lease obligations $ 86 $ 172 $ 172 $ 64 $ — $ — $ 494 Private equity and limited partnerships (1) 6,950 — — — — — 6,950 $ 7,036 $ 172 $ 172 $ 64 $ — $ — $ 7,444 (1) Given the nature of these investments, the Company is unable to determine with any degree of accuracy when these commitments will be called. Therefore, for purposes of the above table, the Company has assumed that all commitments with no fixed payment schedules will be called during the year ending December 31, 2018 . Litigation From time to time, in the normal course of business, the Company may be involved in formal and informal dispute resolution procedures, which may include arbitration or litigation, the outcomes of which determine the rights and obligations under the Company’s reinsurance contracts and other contractual agreements. In some disputes, the Company may seek to enforce its rights under an agreement or to collect funds owing to it. In other matters, the Company may resist attempts by others to collect funds or enforce alleged rights. While the final outcome of legal disputes cannot be predicted with certainty, the Company does not believe that any existing dispute, when finally resolved, will have a material adverse effect on the Company’s business, financial condition or operating results.

SEGMENT REPORTING

SEGMENT REPORTING	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
SEGMENT REPORTING	SEGMENT REPORTING The Company manages its business on the basis of one operating segment, Property & Casualty Reinsurance. The following tables provide a breakdown of the Company’s gross premiums written by line of business and by geographic area of risks insured for the periods indicated: Gross Premiums Written by Line of Business Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) ($ in thousands) Property Commercial $ 3,069 2.2 % $ 2,102 1.2 % $ 5,712 1.8 % $ 5,481 1.5 % Motor 18,391 12.9 14,200 8.1 40,813 12.9 29,509 7.9 Personal 4,884 3.4 20,513 11.7 7,324 2.3 41,782 11.2 Total Property 26,344 18.5 36,815 21.0 53,849 17.0 76,772 20.6 Casualty General Liability 137 0.1 401 0.2 1,370 0.4 2,191 0.6 Motor Liability 72,118 50.7 75,883 43.4 155,680 49.1 152,836 41.1 Professional Liability 673 0.5 2,168 1.2 1,111 0.4 6,221 1.7 Workers' Compensation 3,135 2.2 1,996 1.2 6,694 2.1 7,418 2.0 Multi-line * 22,377 15.8 33,913 19.4 39,392 12.4 67,163 18.0 Total Casualty 98,440 69.3 114,361 65.4 204,247 64.4 235,829 63.4 Other Accident & Health 12,667 8.9 10,406 6.0 42,244 13.3 33,510 9.0 Financial 3,813 2.7 12,931 7.4 15,027 4.7 24,860 6.7 Marine — — — — 371 0.1 — — Other Specialty 845 0.6 376 0.2 1,496 0.5 1,132 0.3 Total Other 17,325 12.2 23,713 13.6 59,138 18.6 59,502 16.0 $ 142,109 100.0 % $ 174,889 100.0 % $ 317,234 100.0 % $ 372,103 100.0 % (*) Contracts that cover more than one line of business are grouped as “multi-line” regardless of whether a portion of the underlying business is covered by one of the lines of business listed above. The Company’s multi-line business predominantly relates to casualty reinsurance. The prior period comparative information has been reclassified to conform to the current period presentation. Gross Premiums Written by Geographic Area of Risks Insured Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) ($ in thousands) U.S. and Caribbean $ 127,475 89.7 % $ 152,014 86.9 % $ 285,182 89.9 % $ 323,772 87.0 % Worldwide (1) 14,603 10.3 22,784 13.0 31,881 10.0 48,078 12.9 Europe 31 — 91 0.1 217 0.1 237 0.1 Asia (2) — — — — (46 ) — 16 — $ 142,109 100.0 % $ 174,889 100.0 % $ 317,234 100.0 % $ 372,103 100.0 % (1) “Worldwide” is comprised of contracts that reinsure risks in more than one geographic area and do not specifically exclude the U.S. (2) The negative balance represents reversal of premiums due to premium adjustments, termination of contracts or premium returned upon novation or commutation of contracts.

ORGANIZATION AND BASIS OF PRE17

ORGANIZATION AND BASIS OF PRESENTATION Reclassification (Policies)	6 Months Ended
	Jun. 30, 2018
Reclassifications [Abstract]
Reclassifications [Text Block]	Reclassifications Prior to the year ended December 31, 2017, the Company presented the redeemable and non-redeemable portion of the non-controlling interest in the related party joint venture under the permanent equity section of the balance sheet. The United States Securities and Exchange Commission (“SEC”) guidance, which is applicable to SEC registrants, requires shares, that are not required to be accounted for in accordance with Financial Accounting Standards Board (“FASB”) ASC Topic Distinguishing Liabilities from Equity , and having redemption features that are not solely within the control of the issuer, to be classified outside of the permanent equity section and instead presented in the mezzanine section of the consolidated balance sheets. Effective from the year ended December 31, 2017, the Company presented the redeemable non-controlling interest in the related party joint venture in the mezzanine section on the Company’s consolidated balance sheet in accordance with the SEC guidance noted above. The comparative condensed consolidated statement of shareholders’ equity for the six months ended June 30, 2017 has been reclassified to conform to the current period presentation of the redeemable non-controlling interest in the related party joint venture. The reclassification had no impact on shareholders’ equity attributable to shareholders or retained earnings. In addition, this change did not impact the condensed consolidated statements of income, earnings per share or condensed consolidated statement of cash flows. See Note 8 for additional information regarding the non-controlling interests in the related party joint venture. Additionally, effective from the three and six month periods ended June 30, 2018, contracts that cover more than one line of business are grouped as “multi-line” regardless of whether a portion of the underlying business is covered by one of the lines of business listed above. The prior period comparative information in Note 10 has been reclassified to conform to the current period presentation.

SIGNIFICANT ACCOUNTING POLICI18

SIGNIFICANT ACCOUNTING POLICIES (Policies)	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of 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 and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the period. Actual results could differ from these estimates.
Restricted Cash and Cash Equivalents	Restricted Cash and Cash Equivalents The Company is required to maintain certain cash in segregated accounts with prime brokers and derivative counterparties. The amount of restricted cash held by prime brokers is primarily used to support the liability created from securities sold, not yet purchased and derivatives. Additionally, restricted cash and cash equivalent balances are held to collateralize regulatory trusts and letters of credit issued to cedents (see Notes 4 and 9 ). The amount of cash encumbered varies depending on the market value of the securities sold, not yet purchased, and the collateral required by the cedents in the form of trust accounts and letters of credit. In addition, derivative counterparties require cash collateral to support the current value of any amounts that may be due to the counterparty based on the value of the underlying financial instrument.
Premium Revenue Recognition	Premium Revenue Recognition The Company accounts for reinsurance contracts in accordance with U.S. GAAP. In the event that a reinsurance contract does not transfer sufficient risk, deposit accounting is used and the contract is reported as a deposit liability. Similarly for ceded contracts that do not transfer sufficient risk, deposit accounting is used and the contract is reported as a deposit asset. The Company writes excess of loss contracts as well as quota share contracts. The Company estimates the ultimate premiums for the entire contract period. These estimates are based on information received from the ceding companies and estimates from actuarial pricing models used by the Company. For excess of loss contracts, the total ultimate estimated premiums are recorded as premiums written at the inception of the contract. For quota share contracts, the premiums are recorded as written based on cession statements from cedents which typically are received monthly or quarterly depending on the terms specified in each contract. For any reporting lag, premiums written are estimated based on the portion of the ultimate estimated premiums relating to the risks underwritten during the lag period. Premium estimates are reviewed by management at least quarterly. Such review includes a comparison of actual reported premiums to expected ultimate premiums along with a review of the aging and collection of premium estimates. Based on management’s review, the appropriateness of the premium estimates is evaluated, and any adjustments to these estimates are recorded in the period in which they are determined. Changes in premium estimates, including premium receivable on both excess of loss and quota share contracts, are expected and may result in significant adjustments in any period. A significant portion of amounts included in reinsurance balances receivable represent estimated premiums written, net of commissions and brokerage, and are not currently due based on the terms of the underlying contracts. Certain contracts allow for reinstatement premiums in the event of a full limit loss prior to the expiry of a contract. A reinstatement premium is not due until there is a loss event and, therefore, in accordance with U.S. GAAP, the Company records a reinstatement premium as written only in the event that a client incurs a loss on the contract and the contract allows for a reinstatement of coverage upon payment of an additional premium. For catastrophe contracts which contractually require the payment of a reinstatement premium upon the occurrence of a loss, the reinstatement premiums are earned over the original contract period. Reinstatement premiums, that are contractually calculated on a pro-rata basis of the original contract period, are earned over the remaining coverage period. For additional premiums which are due on a contract that has no remaining coverage period, the additional premiums are earned in full when due. Certain contracts may provide for a penalty to be paid if the contract is terminated and canceled prior to its expiration term. Cancellation penalties are recognized in the period the notice of cancellation is received and are recorded in the consolidated statements of income under “other income (expense), net”. Premiums written are generally recognized as earned over the contract period in proportion to the period of risk covered. Unearned premiums consist of the unexpired portion of reinsurance provided.
Reinsurance Premiums Ceded	Reinsurance Premiums Ceded The Company reduces the risk of future losses on business assumed by reinsuring certain risks and exposures with other reinsurers (retrocessionaires). The Company remains liable to the extent that any retrocessionaire fails to meet its obligations and to the extent the Company does not hold sufficient security for their unpaid obligations. Ceded premiums are written during the period in which the risks incept and are expensed over the contract period in proportion to the period of protection. Unearned premiums ceded consist of the unexpired portion of reinsurance obtained.
Deferred Acquisition Costs	Deferred Acquisition Costs Policy acquisition costs, such as commission and brokerage costs, relate directly to, and vary with, the writing of reinsurance contracts. Acquisition costs relating solely to bound contracts are deferred subject to ultimate recoverability and are amortized over the related contract term. The Company evaluates the recoverability of deferred acquisition costs by determining if the sum of future earned premiums and anticipated investment income is greater than the expected future claims and expenses. If a loss is probable on the unexpired portion of policies in force, a premium deficiency loss is recognized. At June 30, 2018 and December 31, 2017 , the deferred acquisition costs were considered fully recoverable and no premium deficiency loss was recorded. Acquisition costs also include profit commissions which are expensed when incurred. Profit commissions are calculated and accrued based on the expected loss experience for contracts and recorded when the current loss estimate indicates that a profit commission is probable under the contract terms.
Funds Withheld	Funds Withheld Funds withheld include reinsurance balances retained by the Company on retroceded contracts as collateral in accordance with the contract terms. Any interest expense that the Company incurs while these funds are withheld, is included under net investment income (loss) in the condensed consolidated statements of income.
Loss and Loss Adjustment Expense Reserves and Recoverable	Loss and Loss Adjustment Expense Reserves and Recoverable The Company establishes reserves for contracts based on estimates of the ultimate cost of all losses including losses incurred but not reported (“IBNR”). These estimated ultimate reserves are based on the Company’s own actuarial estimates derived from reports received from ceding companies, industry data and historical experience. These estimates are reviewed by the Company at least quarterly and adjusted as necessary. Since reserves are estimates, the final settlement of losses may vary from the reserves established and any adjustments to the estimates, which may be material, are recorded in the period they are determined. Loss and loss adjustment expenses recoverable include the amounts due from retrocessionaires for unpaid loss and loss adjustment expenses on retrocession agreements. Ceded losses incurred but not reported are estimated based on the Company’s actuarial estimates. These estimates are reviewed periodically and adjusted when deemed necessary. The Company may not be able to ultimately recover the loss and loss adjustment expense recoverable amounts due to the retrocessionaires’ inability to pay. The Company regularly evaluates the financial condition of its retrocessionaires and records provisions for uncollectible reinsurance expenses recoverable when recovery is no longer probable. Consideration paid by the Company for retroactive reinsurance that meets the conditions for reinsurance accounting (e.g. loss portfolio transfers) are reported as loss and loss adjustment expenses recoverable to the extent those amounts do not exceed the associated liabilities. If the amounts paid for retroactive reinsurance exceed the liabilities, the Company increases the related liabilities, at the time the reinsurance contract is effective, and the excess is charged to net income as losses incurred. If the liabilities exceed the amounts paid, the recoverable balance is increased to reflect the difference, and the resulting gain is deferred and amortized over the estimated loss payout period. Changes in the estimated amount of liabilities relating to the underlying reinsured contracts are recognized in net income in the period of the change.
Notes Receivable	Notes Receivable Notes receivable include promissory notes receivable from third party entities. These notes are recorded at cost along with accrued interest, if any, which approximates the fair value. Interest income and realized gains or losses on sale of notes receivable are included under net investment income (loss) in the condensed consolidated statements of income. The Company regularly reviews all notes receivable individually for impairment and records valuation allowance provisions for uncollectible and non-performing notes. The Company places notes on non-accrual status when the recorded value of the note is not considered impaired but there is uncertainty as to the collection of interest in accordance with the terms of the note. For notes receivable placed on non-accrual status, the notes are recorded excluding any accrued interest amount. The Company resumes accrual of interest on a note when none of the principal or interest remains past due, and the Company expects to collect the remaining contractual principal and interest. Interest collected on notes that are placed on non-accrual status is treated on a cash-basis and recorded as interest income when collected, provided that the recorded value of the note is deemed to be fully collectible. Where doubt exists as to the collectability of the remaining recorded value of the notes placed on non-accrual status, any payments received are applied to reduce the recorded value of the notes.
Deposit Assets and Liabilities	Deposit Assets and Liabilities In accordance with U.S. GAAP, deposit accounting is used in the event that a reinsurance contract does not transfer sufficient insurance risk. The deposit method of accounting requires an asset or liability to be recognized based on the consideration paid or received. The deposit asset or liability balance is subsequently adjusted using the interest method with a corresponding income or expense recorded in the condensed consolidated statements of income as other income or expense. The Company’s deposit assets and liabilities are recorded in the condensed consolidated balance sheets under reinsurance balances receivable and reinsurance balances payable, respectively.
Financial Instruments	Financial Instruments Investments in Securities and Investments in Securities Sold, Not Yet Purchased The Company’s investments in debt instruments and equity securities that are classified as “trading securities” are carried at fair value. The fair values of the listed equity investments are derived based on quoted prices (unadjusted) in active markets for identical assets (Level 1 inputs). The fair values of listed equities that have restrictions on sale or transfer which expire within one year, are determined by adjusting the observed market price of the equity using a liquidity discount based on observable market inputs. The fair values of debt instruments are derived based on inputs that are observable, either directly or indirectly, such as market maker or broker quotes reflecting recent transactions (Level 2 inputs), and are generally derived based on the average of multiple market maker or broker quotes which are considered to be binding. Where quotes are not available, debt instruments are valued using cash flow models using assumptions and estimates that may be subjective and non-observable (Level 3 inputs). The Company’s “other investments” may include investments in private and unlisted equity securities, limited partnerships and commodities, which are all carried at fair value. The fair values of commodities are determined based on quoted prices in active markets for identical assets (Level 1). The Company maximizes the use of observable direct or indirect inputs (Level 2 inputs) when deriving the fair values for “other investments”. For limited partnerships and private and unlisted equity securities, where observable inputs are not available, the fair values are derived based on unobservable inputs (Level 3 inputs) such as management’s assumptions developed from available information using the services of the investment advisor, including the most recent net asset values obtained from the managers of those underlying investments. For certain private equity fund investments, the Company has elected to measure the fair value using the net asset value practical expedient allowed under U.S. GAAP, and, accordingly, these investments are not classified as Level 1, 2 or 3 in the fair value hierarchy. For securities classified as “trading securities” and “other investments”, any realized and unrealized gains or losses are determined on the basis of the specific identification method (by reference to cost or amortized cost, as appropriate) and included in net investment income (loss) in the condensed consolidated statements of income. Dividend income and expense are recorded on the ex-dividend date. The ex-dividend date is the date as of when the underlying security must have been traded to be eligible for the dividend declared. Interest income and interest expense are recorded on an accrual basis.
Derivative Financial Instruments	Derivative Financial Instruments U.S. GAAP requires that an entity recognize all derivatives in the balance sheet at fair value. It also requires that unrealized gains and losses resulting from changes in fair value be included in income or comprehensive income, depending on whether the instrument qualifies as a hedge transaction, and if so, the type of hedge transaction. The Company’s derivative financial instrument assets are included in financial contracts receivable. Derivative financial instrument liabilities are generally included in financial contracts payable. The Company’s derivatives do not qualify as hedges for financial reporting purposes and are recorded in the condensed consolidated balance sheets on a gross basis and not offset against any collateral pledged or received. Pursuant to the International Swaps and Derivatives Association (“ISDA”) master agreements, securities lending agreements and other agreements, the Company and its counterparties typically have the ability to net certain payments owed to each other in specified circumstances. In addition, in the event a party to one of the ISDA master agreements, securities lending agreements or other agreements defaults, or a transaction is otherwise subject to termination, the non-defaulting party generally has the right to set off outstanding balances due from the defaulting party against payments owed to the defaulting party or collateral held by the non-defaulting party. The Company may, from time to time, enter into underwriting contracts such as industry loss warranty contracts (“ILW”) that are treated as derivatives for U.S GAAP purposes. Financial Contracts The Company enters into financial contracts with counterparties as part of its investment strategy. Financial contracts, which include total return swaps, credit default swaps (“CDS”), futures, options, currency forwards and other derivative instruments, are recorded at their fair value with any unrealized gains and losses included in net investment income (loss) in the condensed consolidated statements of income. Financial contracts receivable represents derivative contracts whereby, based upon the contract’s current fair value, the Company will be entitled to receive payments upon settlement of the contract. Financial contracts payable represents derivative contracts whereby, based upon each contract’s current fair value, the Company will be obligated to make payments upon settlement of the contract. Total return swap agreements, included on the condensed consolidated balance sheets as financial contracts receivable and financial contracts payable, are derivative financial instruments whereby the Company is either entitled to receive or obligated to pay the product of a notional amount multiplied by the movement in an underlying security, which the Company may not own, over a specified time frame. In addition, the Company may also be obligated to pay or receive other payments based on interest rates, dividend payments and receipts, or foreign exchange movements during a specified period. The Company measures its rights or obligations to the counterparty based on the fair value movements of the underlying security together with any other payments due. These contracts are carried at fair value, based on observable inputs (Level 2 inputs) with the resultant unrealized gains and losses reflected in net investment income (loss) in the condensed consolidated statements of income. Additionally, any changes in the value of amounts received or paid on swap contracts are reported as a gain or loss in net investment income (loss) in the condensed consolidated statements of income. Financial contracts may also include exchange traded futures or options contracts that are based on the movement of a particular index, equity security, commodity, currency or interest rate. Where such contracts are traded in an active market, the Company’s obligations or rights on these contracts are recorded at fair value based on the observable quoted prices of the same or similar financial contracts in an active market (Level 1) or on broker quotes which reflect market information based on actual transactions (Level 2). Amounts invested in exchange traded options and over the counter (“OTC”) options are recorded either as an asset or liability at inception. Subsequent to initial recognition, unexpired exchange traded option contracts are recorded at fair value based on quoted prices in active markets (Level 1). For OTC options or exchange traded options where a quoted price in an active market is not available, fair values are derived based upon observable inputs (Level 2) such as multiple quotes from brokers and market makers, which are considered to be binding. The Company may purchase and sell CDS for strategic investment purposes. A CDS is a derivative instrument that provides protection against an investment loss due to specified credit or default events of a reference entity. The seller of a CDS guarantees to pay the buyer a specified amount if the reference entity defaults on its obligations or fails to perform. The buyer of a CDS pays a premium over time to the seller in exchange for obtaining this protection. A CDS trading in an active market is valued at fair value based on broker or market maker quotes for identical instruments in an active market (Level 2) or based on the current credit spreads on identical contracts (Level 2).
Share-based Compensation	Share-Based Compensation The Company has established a stock incentive plan for directors, employees and consultants. U.S. GAAP requires the Company to recognize share-based compensation transactions using the fair value at the grant date of the award. The Company measures compensation for restricted shares and restricted stock units (“RSUs”) based on the price of the Company’s common shares at the grant date. For restricted shares and RSUs with both service and performance vesting conditions, the expense is recognized based on management’s estimate of the probability of the performance conditions being achieved based on historical results and expectations of future results. If the performance conditions is expected to be met, the expense is attributed to the period for which the requisite service has been rendered. For restricted shares and RSUs with only service vesting conditions, the expense is recognized on a straight line basis over the vesting period, net of any estimated or expected forfeitures. The forfeiture rate is estimated based on the Company’s historical actual forfeitures relating to restricted shares and RSUs granted to employees. The forfeiture rate is reviewed annually and adjusted as necessary. No forfeiture rate is used for restricted shares granted to directors which vest over a twelve-month period. Determining the fair value of share purchase options at the grant date requires significant estimation and judgment. The Company uses an option-pricing model (Black-Scholes option pricing model) to assist in the calculation of fair value for share purchase options. The model requires estimation of various inputs such as estimated term, forfeiture and dividend rates and expected volatility. In determining the grant date fair value, the Company uses the full life of the options, ten years, as the estimated term of the options, and has assumed no forfeitures and no dividends paid during the life of the options. The estimate of expected volatility is based on the daily historical trading data of the Company’s Class A ordinary shares from the date that these shares commenced trading (May 24, 2007) to the grant date. For share purchase options issued under the employee stock incentive plan, the compensation cost is calculated and expensed over the vesting periods on a graded vesting basis (see Note 7 ). If actual results differ significantly from these estimates and assumptions, particularly in relation to the Company’s estimation of volatility which requires the most judgment, share-based compensation expense, primarily with respect to future share-based awards, could be materially impacted.
Foreign Exchange	Foreign Exchange The reporting and functional currency of the Company and all its subsidiaries is the U.S. dollar. Transactions in foreign currencies are recorded in U.S. dollars at the exchange rates in effect on the transaction date. Monetary assets and liabilities in foreign currencies at the balance sheet date are translated at the exchange rate in effect at the balance sheet date and translation exchange gains and losses, if any, are included in “other income (expense), net” in the condensed consolidated statements of income.
Comprehensive Income (Loss)	Comprehensive Income (Loss) The Company has no comprehensive income or loss, other than the net income or loss disclosed in the condensed consolidated statements of income.
Earnings (Loss) Per Share	Earnings (Loss) Per Share Basic earnings per share are based on the weighted average number of common shares and participating securities outstanding during the period. Diluted earnings per share includes the dilutive effect of restricted stock units (“RSU”) and additional potential common shares issuable when stock options are exercised and are determined using the treasury stock method. The Company treats its unvested restricted stock as participating securities in accordance with U.S. GAAP, which requires that unvested stock awards which contain non-forfeitable rights to dividends or dividend equivalents, whether paid or unpaid (referred to as “participating securities”), be included in the number of shares outstanding for both basic and diluted earnings per share calculations. In the event of a net loss, all RSUs, stock options outstanding and participating securities are excluded from the calculation of both basic and diluted loss per share since their inclusion would be anti-dilutive.
Taxation	Taxation Under current Cayman Islands law, no corporate entity, including GLRE and Greenlight Re, is obligated to pay taxes in the Cayman Islands on either income or capital gains. The Company has an undertaking from the Governor-in-Cabinet of the Cayman Islands, pursuant to the provisions of the Tax Concessions Law, as amended, that, in the event that the Cayman Islands enacts any legislation that imposes tax on profits, income, gains or appreciations, or any tax in the nature of estate duty or inheritance tax, such tax will not be applicable to GLRE, Greenlight Re nor their respective operations, or to the Class A or Class B ordinary shares or related obligations, until February 1, 2025. Verdant is incorporated in Delaware and, therefore, is subject to taxes in accordance with the U.S. federal rates and regulations prescribed by the U.S. Internal Revenue Service (“IRS”). Verdant’s taxable income is generally expected to be taxed at a marginal rate of 21% . Verdant’s tax years 2014 and beyond, remain open and subject to examination by the IRS. GRIL is incorporated in Ireland and, therefore, is subject to the Irish corporation tax rate of 12.5% on its trading income, and 25% on its non-trading income, if any. Any deferred tax asset is evaluated for recovery and a valuation allowance is recorded when it is more likely than not that the deferred tax asset will not be realized in the future. The Company has not taken any income tax positions that are subject to significant uncertainty or that are reasonably likely to have a material impact on the Company.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In January 2016, the FASB issued ASU 2016-01, “Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”) . The new guidance is intended to improve the recognition and measurement of financial instruments. ASU 2016-01, among other things, requires equity investments to be measured at fair value with changes in fair value recognized in net income or loss, requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes and requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset. ASU 2016-01 affects public and private companies, not-for-profit organizations, and employee benefit plans that hold financial assets or owe financial liabilities. The new guidance is effective for public companies for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted ASU 2016-01 during the first quarter of fiscal year 2018 and the adoption of this guidance did not have any significant impact on the Company’s net income or loss or retained earnings since the Company’s investments are classified as “trading” and the unrealized gains and losses are recognized in net income or loss. The Company has implemented the new disclosures required under ASU 2016-01 commencing from the first quarter of 2018. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”) . Under the new guidance, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. ASU 2016-02 is effective for public companies for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted for any organization in any interim or annual period. The Company currently has operating leases for its office spaces as disclosed in Note 9 of the condensed consolidated financial statements which will be recognized as right-of-use asset upon adoption of ASU 2016-02. The Company is in the process of evaluating the impact of adopting ASU 2016-02 on the Company’s consolidated financial statements and anticipates implementing ASU 2016-02 during the first quarter of fiscal year 2019. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurements of Credit Losses on Financial Instruments” (“ASU 2016-13”) . ASU 2016-13 amends the guidance on reporting credits losses and affects loans, debt securities, trade receivables, reinsurance recoverables and other financial assets that have the contractual right to receive cash. The amendments are effective for annual periods beginning after December 15, 2019, and interim periods within those annual periods. Early adoption is permitted for any organization for annual periods beginning after December 15, 2018 and interim periods within those annual periods. The Company is in the process of evaluating the impact of the requirements of ASU 2016-13 on the Company’s consolidated financial statements and anticipates implementing ASU 2016-13 during the first quarter of fiscal year 2020. In November 2016, the FASB issued ASU 2016-18, “Statements of Cash Flows - Restricted Cash (Topic 230)” (“ASU 2016-18”). ASU 2016-18 requires restricted cash and cash equivalents to be included with cash and cash equivalents in the statement of cash flows and the nature of the restrictions on cash and cash equivalents to be disclosed. ASU 2016-18 is effective for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption was permitted. The Company adopted ASU 2016-18 during the first quarter of fiscal year 2018 and amended the presentation in the statement of cash flows to include the restricted cash and cash equivalents with cash and cash equivalents in the condensed consolidated statements of cash flows and retrospectively reclassified comparative periods presented. The adoption had no impact on the Company’s net income or loss or retained earnings. The FASB has issued ASU No. 2014-09, “Revenue from Contracts with Customers”, and related amendments, ASU 2015-14, ASU 2016-10, ASU 2016-12, ASU 2016-20, ASU 2017-05 and ASU 2017-13, (collectively, “Topic 606”). Topic 606 creates a new comprehensive revenue recognition standard that will serve as a single source of revenue guidance for all companies that either enter into contracts with customers to transfer goods or services or enter into contracts for the transfer of non-financial assets, unless those contracts are within the scope of other standards, such as insurance contracts. Topic 606 becomes effective for annual periods beginning after December 15, 2017, and interim periods within those fiscal years. The Company adopted Topic 606 during the first quarter of the fiscal year 2018, and since all of the Company’s revenues relate to reinsurance contracts and investment income, the adoption of Topic 606 did not have a material impact on the Company’s revenues and related disclosures.

SIGNIFICANT ACCOUNTING POLICI19

SIGNIFICANT ACCOUNTING POLICIES (Tables)	6 Months Ended
	Jun. 30, 2018
Accounting Policies [Abstract]
Schedule of Weighted Average Number of Shares	Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 Weighted average shares outstanding - basic 36,952,472 37,025,703 36,950,828 37,009,539 Effect of dilutive employee and director share-based awards — — — — Weighted average shares outstanding - diluted 36,952,472 37,025,703 36,950,828 37,009,539 Anti-dilutive stock options outstanding 1,015,627 458,741 1,015,627 358,741 Participating securities excluded from calculation of loss per share 462,787 330,102 462,787 330,102

FINANCIAL INSTRUMENTS (Tables)

FINANCIAL INSTRUMENTS (Tables)		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fair Value Hierarchy		The following table presents the Company’s investments, categorized by the level of the fair value hierarchy as of June 30, 2018 : Fair value measurements as of June 30, 2018 Description Quoted prices in Significant other Significant Total ($ in thousands) Assets: Debt instruments $ — $ 12,899 $ 932 $ 13,831 Listed equity securities 809,826 10,667 — 820,493 Commodities 36,225 — — 36,225 Private and unlisted equity securities — — 6,909 6,909 $ 846,051 $ 23,566 $ 7,841 $ 877,458 Unlisted equity funds measured at net asset value (1) 26,117 Total investments $ 903,575 Financial contracts receivable $ 892 $ 67,231 $ — $ 68,123 Liabilities: Listed equity securities, sold not yet purchased $ (570,861 ) $ — $ — $ (570,861 ) Debt instruments, sold not yet purchased — (110,417 ) — (110,417 ) Total securities sold, not yet purchased $ (570,861 ) $ (110,417 ) $ — $ (681,278 ) Financial contracts payable $ (2,504 ) $ (16,242 ) $ — $ (18,746 ) (1) Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets. The following table presents the Company’s investments, categorized by the level of the fair value hierarchy as of December 31, 2017 : Fair value measurements as of December 31, 2017 Description Quoted prices in Significant other Significant Total ($ in thousands) Assets: Debt instruments $ — $ 6,300 $ 880 $ 7,180 Listed equity securities 1,181,150 22,522 — 1,203,672 Commodities 121,502 — — 121,502 Private and unlisted equity securities — — 6,108 6,108 $ 1,302,652 $ 28,822 $ 6,988 $ 1,338,462 Unlisted equity funds measured at net asset value (1) 24,522 Total investments $ 1,362,984 Financial contracts receivable $ 22 $ 12,871 $ — $ 12,893 Liabilities: Listed equity securities, sold not yet purchased $ (812,652 ) $ — $ — $ (812,652 ) Debt instruments, sold not yet purchased — (100,145 ) — (100,145 ) Total securities sold, not yet purchased $ (812,652 ) $ (100,145 ) $ — $ (912,797 ) Financial contracts payable $ — $ (22,222 ) $ — $ (22,222 ) (1) Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.
Fair Value Measurements Using Significant Unobservable Inputs		The following tables present the reconciliation of the balances for all investments measured at fair value using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2018 : Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Three months ended June 30, 2018 Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 885 $ 6,135 $ 7,020 Purchases — 800 800 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 47 (26 ) 21 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 932 $ 6,909 $ 7,841 Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six months ended June 30, 2018 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 880 $ 6,108 $ 6,988 Purchases — 800 800 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 52 1 53 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 932 $ 6,909 $ 7,841	The following tables present the reconciliation of the balances for all investments measured at fair value using significant unobservable inputs (Level 3) for the three and six months ended June 30, 2017 : Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Three months ended June 30, 2017 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 704 $ 6,076 $ 6,780 Purchases — — — Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 72 9 81 Transfers into Level 3 — — — Transfers out of Level 3 — — — Ending balance $ 776 $ 6,085 $ 6,861 Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Six months ended June 30, 2017 Assets Debt instruments Private and unlisted equity securities Total ($ in thousands) Beginning balance $ 654 $ 6,109 $ 6,763 Purchases — 1,750 1,750 Sales — — — Issuances — — — Settlements — — — Total realized and unrealized gains (losses) and amortization included in earnings, net 122 (6 ) 116 Transfers into Level 3 — — — Transfers out of Level 3 — (1,768 ) (1,768 ) Ending balance $ 776 $ 6,085 $ 6,861
Maturity Distribution for Debt Instruments		The maturity distribution for debt instruments held at June 30, 2018 and December 31, 2017 was as follows: June 30, 2018 December 31, 2017 Cost/ Fair Cost/ Fair ($ in thousands) Within one year $ 1,551 $ 234 $ 7,557 $ 441 From one to five years 892 217 — — From five to ten years 2,859 1,324 2,109 52 More than ten years 7,434 12,056 6,782 6,687 $ 12,736 $ 13,831 $ 16,448 $ 7,180
Other Investments		At June 30, 2018 , the following securities were included in other investments: Cost Unrealized Unrealized Fair ($ in thousands) Commodities $ 29,493 $ 6,732 $ — $ 36,225 Private and unlisted equity funds 25,803 7,223 — 33,026 $ 55,296 $ 13,955 $ — $ 69,251 At December 31, 2017 , the following securities were included in other investments: Cost Unrealized Unrealized Fair ($ in thousands) Commodities $ 101,184 $ 20,318 $ — $ 121,502 Private and unlisted equity funds 25,316 5,314 — 30,630 $ 126,500 $ 25,632 $ — $ 152,132
Investments in Securities Sold, Not Yet Purchased		Investments in Securities Sold, Not Yet Purchased Securities sold, not yet purchased, are securities that the Company has sold, but does not own, in anticipation of a decline in the market value of the security. The Company’s risk is that the value of the security will increase rather than decline. Consequently, the settlement amount of the liability for securities sold, not yet purchased, may exceed the amount recorded in the condensed consolidated balance sheet as the Company is obligated to purchase the securities sold, not yet purchased, in the market at prevailing prices to settle its obligations. To establish a position in a security sold, not yet purchased, the Company needs to borrow the security for delivery to the buyer. On each day the transaction is open, the liability for the obligation to replace the borrowed security is marked-to-market and an unrealized gain or loss is recorded. At the time the transaction is closed, the Company realizes a gain or loss equal to the difference between the price at which the security was sold and the cost of replacing the borrowed security. While the transaction is open, the Company will also incur an expense for any dividends or interest which will be paid to the lender of the securities. At June 30, 2018 , the following securities were included in investments in securities sold, not yet purchased: Proceeds Unrealized gains Unrealized losses Fair value ($ in thousands) Corporate debt – U.S. $ (8,779 ) $ — $ (279 ) $ (9,058 ) Equities – listed (456,038 ) 6,163 (120,987 ) (570,862 ) Sovereign debt – Non U.S. (96,230 ) — (5,128 ) (101,358 ) $ (561,047 ) $ 6,163 $ (126,394 ) $ (681,278 ) At December 31, 2017 , the following securities were included in investments in securities sold, not yet purchased: Proceeds Unrealized gains Unrealized losses Fair value ($ in thousands) Equities – listed $ (643,148 ) $ 17,541 $ (187,045 ) $ (812,652 ) Sovereign debt – Non U.S. (96,231 ) — (3,914 ) (100,145 ) $ (739,379 ) $ 17,541 $ (190,959 ) $ (912,797 )
Fair values of Financial Contracts Outstanding	[1],[2],[3]	At June 30, 2018 , the fair values of financial contracts outstanding were as follows: Financial Contracts Listing (1) Notional amount of Fair value of net assets ($ in thousands) Financial contracts receivable Commodity Swaps USD 33,924 $ 1,575 Futures USD 45,588 892 Interest rate options USD 1,783,000 1,296 Interest rate swaps JPY 21,652 93 Put options USD 126,059 52,946 Total return swaps – equities EUR/GBP/KRW/USD 93,762 11,321 Total financial contracts receivable, at fair value $ 68,123 Financial contracts payable Forwards KRW 56,810 $ (1,775 ) Futures USD 69,839 (2,504 ) Put options USD 24,565 (13,014 ) Total return swaps – equities EUR/RON 17,207 (1,453 ) Total financial contracts payable, at fair value $ (18,746 ) (1) USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu. At December 31, 2017 , the fair values of financial contracts outstanding were as follows: Financial Contracts Listing currency (1) Notional amount of Fair value of net assets ($ in thousands) Financial contracts receivable Call options USD 2,656 $ 91 Commodity Swaps USD 17,833 2,142 Forwards KRW 41,379 801 Futures USD 5,874 12 Interest rate swaps JPY 21,269 479 Put options (2) USD 155 1 Total return swaps – equities EUR/GBP/USD 34,965 9,357 Warrants and rights on listed equities EUR/USD 29 10 Total financial contracts receivable, at fair value $ 12,893 Financial contracts payable Commodity Swaps USD 26,795 $ (353 ) Put options USD 130 (14 ) Total return swaps – equities EUR/GBP/KRW/RON/USD 60,663 (21,855 ) Total financial contracts payable, at fair value $ (22,222 ) (1) USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu. (2) Includes options on the Chinese Yuan, denominated in U.S. dollars.
Gain (Loss) on derivatives recognized in income		During the three and six months ended June 30, 2018 and 2017 , the Company reported gains and losses on derivatives as follows: Derivatives not designated as hedging instruments Location of gains and losses on derivatives recognized in income Gain (loss) on derivatives recognized in income Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) Forwards Net investment income (loss) $ (2,784 ) $ (289 ) $ (2,907 ) $ 334 Futures Net investment income (loss) (6,003 ) 110 (7,952 ) (403 ) Interest rate options Net investment income (loss) (517 ) — (1,154 ) — Interest rate swaps Net investment income (loss) (118 ) (198 ) (449 ) (93 ) Options, warrants, and rights Net investment income (loss) (14,929 ) (4,584 ) (13,842 ) (12,112 ) Commodity swaps Net investment income (loss) 2,308 (3,746 ) 4,156 (10,705 ) Total return swaps – equities Net investment income (loss) 9,793 (10,593 ) (9,238 ) (282 ) Total $ (12,250 ) $ (19,300 ) $ (31,386 ) $ (23,261 )
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]		For the three and six months ended June 30, 2018 , the Company’s volume of derivative activities (based on notional amounts) was as follows: 2018 Three months ended June 30 Six months ended June 30 Derivatives not designated as hedging instruments (notional amounts) Entered Exited Entered Exited ($ in thousands) Forwards $ 9,156 $ 14,438 $ 63,528 $ 47,766 Futures 110,201 76,814 423,374 312,712 Interest rate options (1) 679,000 — 1,783,000 — Options, warrants and rights (1) 73,406 9,280 245,986 26,646 Commodity swaps 34,792 20,948 34,792 49,923 Total return swaps 8,256 13,161 16,850 32,139 Total $ 914,811 $ 134,641 $ 2,567,530 $ 469,186 (1) Exited amount excludes derivatives which expired or were exercised during the period. For the three and six months ended June 30, 2017 , the Company’s volume of derivative activities (based on notional amounts) was as follows: 2017 Three months ended June 30 Six months ended June 30 Derivatives not designated as hedging instruments (notional amounts) Entered Exited Entered Exited ($ in thousands) Forwards $ 164 $ — $ 3,640 $ — Futures 2,890 5,818 32,400 29,887 Options, warrants and rights (1) 229,999 — 577,917 110,102 Commodity swaps 2,025 8,406 2,025 16,588 Total return swaps 11,377 235,806 243,495 296,413 Total $ 246,455 $ 250,030 $ 859,477 $ 452,990 (1) Exited amount excludes derivatives which expired or were exercised during the period.
Offsetting assets and liabilities		As of June 30, 2018 , the gross and net amounts of derivative instruments and the cash collateral applicable to derivative instruments were as follows: June 30, 2018 (i) (ii) (iii) = (i) - (ii) (iv) Gross amounts not offset in the balance sheet (v) = (iii) + (iv) Description Gross amounts of recognized assets (liabilities) Gross amounts offset in the balance sheet Net amounts of assets (liabilities) presented in the balance sheet Financial instruments available for offset Cash collateral (received) pledged Net amount of asset (liability) ($ in thousands) Financial contracts receivable $ 68,123 $ — $ 68,123 $ (15,359 ) $ (22,933 ) $ 29,831 Financial contracts payable (18,746 ) — (18,746 ) 15,359 — (3,387 ) As of December 31, 2017 , the gross and net amounts of derivative instruments and the cash collateral applicable to derivative instruments were as follows: December 31, 2017 (i) (ii) (iii) = (i) - (ii) (iv) Gross amounts not offset in the balance sheet (v) = (iii) + (iv) Description Gross amounts of recognized assets (liabilities) Gross amounts offset in the balance sheet Net amounts of assets (liabilities) presented in the balance sheet Financial instruments available for offset Cash collateral (received) pledged Net amount of asset (liability) ($ in thousands) Financial contracts receivable $ 12,893 $ — $ 12,893 $ (5,128 ) $ (1,336 ) $ 6,429 Financial contracts payable (22,222 ) — (22,222 ) 5,128 17,094 —
Debt instruments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading securities, Debt and Equities		Debt instruments, trading At June 30, 2018 , the following investments were included in debt instruments: Cost/amortized cost Unrealized gains Unrealized losses Fair ($ in thousands) Corporate debt – U.S. $ 3,186 $ — $ (2,170 ) $ 1,016 Corporate debt – Non U.S. 2,109 — (2,099 ) 10 Municipal debt – U.S. 7,441 5,364 — 12,805 Total debt instruments $ 12,736 $ 5,364 $ (4,269 ) $ 13,831 At December 31, 2017 , the following investments were included in debt instruments: Cost/amortized cost Unrealized gains Unrealized losses Fair ($ in thousands) Corporate debt – U.S. $ 8,508 $ — $ (7,186 ) $ 1,322 Corporate debt – Non U.S. 2,109 — (2,057 ) 52 Municipal debt – U.S. 5,831 — (25 ) 5,806 Total debt instruments $ 16,448 $ — $ (9,268 ) $ 7,180
Total equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading securities, Debt and Equities		At June 30, 2018 , the following long positions were included in equity securities, trading: Cost Unrealized Unrealized Fair ($ in thousands) Equities – listed $ 754,110 $ 121,165 $ (54,782 ) $ 820,493 Total equity securities $ 754,110 $ 121,165 $ (54,782 ) $ 820,493 At December 31, 2017 , the following long positions were included in equity securities, trading: Cost Unrealized Unrealized Fair ($ in thousands) Equities – listed $ 1,014,426 $ 208,350 $ (19,104 ) $ 1,203,672 Total equity securities $ 1,014,426 $ 208,350 $ (19,104 ) $ 1,203,672
[1]	Includes options on the Chinese Yuan, denominated in U.S. dollars.
[2]	USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu.
[3]	USD = US Dollar; EUR = Euro; GBP = British Pound; JPY = Japanese Yen; KRW = Korean Won; RON = Romanian New Leu.

LOSS AND LOSS ADJUSTMENT EXPE21

LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES (Tables)	6 Months Ended
	Jun. 30, 2018
Insurance Loss Reserves [Abstract]
Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block]	At June 30, 2018 and December 31, 2017 , loss and loss adjustment expense reserves were comprised of the following: Consolidated June 30, 2018 December 31, 2017 ($ in thousands) Case reserves $ 170,389 $ 178,088 IBNR 303,949 286,292 Total $ 474,338 $ 464,380 At June 30, 2018 and December 31, 2017 , the loss and loss adjustment expense reserves relating to health were $24.7 million and $22.2 million , respectively. A summary of changes in outstanding loss and loss adjustment expense reserves for the six months ended June 30, 2018 and 2017 is as follows: Consolidated 2018 2017 ($ in thousands) Gross balance at January 1 $ 464,380 $ 306,641 Less: Losses recoverable (29,459 ) (2,704 ) Net balance at January 1 434,921 303,937 Incurred losses related to: Current year 184,102 203,922 Prior years (3,463 ) 6,906 Total incurred 180,639 210,828 Paid losses related to: Current year (55,909 ) (60,134 ) Prior years (121,609 ) (99,763 ) Total paid (177,518 ) (159,897 ) Foreign currency revaluation (709 ) 1,826 Net balance at June 30 437,333 356,694 Add: Losses recoverable 37,005 2,661 Gross balance at June 30 $ 474,338 $ 359,355 The changes in the outstanding loss and loss adjustment expense reserves for health claims for the six months ended June 30, 2018 and 2017 are as follows: Health 2018 2017 ($ in thousands) Gross balance at January 1 $ 22,181 $ 18,993 Less: Losses recoverable — — Net balance at January 1 22,181 18,993 Incurred losses related to: Current year 27,046 21,674 Prior years 765 (384 ) Total incurred 27,811 21,290 Paid losses related to: Current year (8,740 ) (7,704 ) Prior years (16,564 ) (14,637 ) Total paid (25,304 ) (22,341 ) Foreign currency revaluation — — Net balance at June 30 24,688 17,942 Add: Losses recoverable — — Gross balance at June 30 $ 24,688 $ 17,942

SHARE-BASED COMPENSATION (Table

SHARE-BASED COMPENSATION (Tables)	6 Months Ended
	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Compensation, Stock Options, Activity	Employee and director stock option activity during the six months ended June 30, 2018 was as follows: Number of Weighted Weighted Intrinsic value ($ in millions) Weighted average remaining contractual term Balance at December 31, 2017 1,015,627 $ 23.55 $ 9.89 $ — 6.9 years Granted — — — Exercised — — — Forfeited — — — Expired — — — Balance at June 30, 2018 1,015,627 $ 23.55 $ 9.89 $ — 6.4 years
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	Number of Weighted Balance at December 31, 2017 331,510 $ 23.45 Granted 245,975 15.78 Vested (100,384 ) 27.74 Forfeited (14,314 ) 21.61 Balance at June 30, 2018 462,787 $ 18.50
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	Employee RSU activity during the six months ended June 30, 2018 was as follows: Number of Weighted Balance at December 31, 2017 22,798 $ 23.50 Granted 28,301 15.90 Vested (4,053 ) 32.21 Forfeited (648 ) 21.65 Balance at June 30, 2018 46,398 $ 18.13

RELATED PARTY TRANSACTIONS Nonc

RELATED PARTY TRANSACTIONS Noncontolling Interest (Tables)	6 Months Ended
	Jun. 30, 2018
Noncontrolling Interest [Line Items]
Noncontrolling Interest Disclosure [Text Block]	Redeemable non-controlling interest in related party joint venture Non-controlling interest in related party joint venture Total non-controlling interest in related party joint venture Six months ended June 30 Six months ended June 30 Six months ended June 30 2018 2017 2018 2017 2018 2017 Opening balance $ 7,169 $ 5,884 — $ 12,933 $ 11,561 — $ 20,102 $ 17,445 Income (loss) attributed to non-controlling interest (1,079 ) (97 ) — (1,868 ) (201 ) — (2,947 ) (298 ) Net contribution into (withdrawal from) non-controlling interest 346 (420 ) — (346 ) 420 — — — Ending balance $ 6,436 $ 5,367 $ 10,719 $ 11,780 $ 17,155 $ 17,147

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	6 Months Ended
	Jun. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Letters of Credit Facilities	At June 30, 2018 , the Company had the following letter of credit facilities, which automatically renew each year unless terminated by either party in accordance with the applicable required notice period: Facility Termination Date Notice period required for termination ($ in thousands) Butterfield Bank (Cayman) Limited $ 50,000 June 30, 2019 90 days prior to termination date Citibank Europe plc 400,000 October 11, 2019 120 days prior to termination date $ 450,000
Schedule of Commitments and Contingencies, Fiscal Year Maturity Schedule	Schedule of Commitments and Contingencies The following is a schedule of future minimum payments required under the above commitments: 2018 2019 2020 2021 2022 Thereafter Total ($ in thousands) Operating lease obligations $ 86 $ 172 $ 172 $ 64 $ — $ — $ 494 Private equity and limited partnerships (1) 6,950 — — — — — 6,950 $ 7,036 $ 172 $ 172 $ 64 $ — $ — $ 7,444 (1) Given the nature of these investments, the Company is unable to determine with any degree of accuracy when these commitments will be called. Therefore, for purposes of the above table, the Company has assumed that all commitments with no fixed payment schedules will be called during the year ending December 31, 2018 .

SEGMENT REPORTING (Tables)

SEGMENT REPORTING (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Gross Premiums Written by Line of Business	The following tables provide a breakdown of the Company’s gross premiums written by line of business and by geographic area of risks insured for the periods indicated: Gross Premiums Written by Line of Business Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) ($ in thousands) Property Commercial $ 3,069 2.2 % $ 2,102 1.2 % $ 5,712 1.8 % $ 5,481 1.5 % Motor 18,391 12.9 14,200 8.1 40,813 12.9 29,509 7.9 Personal 4,884 3.4 20,513 11.7 7,324 2.3 41,782 11.2 Total Property 26,344 18.5 36,815 21.0 53,849 17.0 76,772 20.6 Casualty General Liability 137 0.1 401 0.2 1,370 0.4 2,191 0.6 Motor Liability 72,118 50.7 75,883 43.4 155,680 49.1 152,836 41.1 Professional Liability 673 0.5 2,168 1.2 1,111 0.4 6,221 1.7 Workers' Compensation 3,135 2.2 1,996 1.2 6,694 2.1 7,418 2.0 Multi-line * 22,377 15.8 33,913 19.4 39,392 12.4 67,163 18.0 Total Casualty 98,440 69.3 114,361 65.4 204,247 64.4 235,829 63.4 Other Accident & Health 12,667 8.9 10,406 6.0 42,244 13.3 33,510 9.0 Financial 3,813 2.7 12,931 7.4 15,027 4.7 24,860 6.7 Marine — — — — 371 0.1 — — Other Specialty 845 0.6 376 0.2 1,496 0.5 1,132 0.3 Total Other 17,325 12.2 23,713 13.6 59,138 18.6 59,502 16.0 $ 142,109 100.0 % $ 174,889 100.0 % $ 317,234 100.0 % $ 372,103 100.0 %
Gross Premiums Written by Geographic Area of Risks Insured	Gross Premiums Written by Geographic Area of Risks Insured Three months ended June 30 Six months ended June 30 2018 2017 2018 2017 ($ in thousands) ($ in thousands) U.S. and Caribbean $ 127,475 89.7 % $ 152,014 86.9 % $ 285,182 89.9 % $ 323,772 87.0 % Worldwide (1) 14,603 10.3 22,784 13.0 31,881 10.0 48,078 12.9 Europe 31 — 91 0.1 217 0.1 237 0.1 Asia (2) — — — — (46 ) — 16 — $ 142,109 100.0 % $ 174,889 100.0 % $ 317,234 100.0 % $ 372,103 100.0 % (1) “Worldwide” is comprised of contracts that reinsure risks in more than one geographic area and do not specifically exclude the U.S. (2) The negative balance represents reversal of premiums due to premium adjustments, termination of contracts or premium returned upon novation or commutation of contracts.

SIGNIFICANT ACCOUNTING POLICI26

SIGNIFICANT ACCOUNTING POLICIES Cash Flow, Supplemental cash equivalents reconciliation (Details)	6 Months Ended
	Jun. 30, 2018
Cash, cash equivalents and restricted cash supplemental [Abstract]
Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]	June 30, 2018 December 31, 2017 ($ in thousands) Cash and cash equivalents $ 65,441 $ 27,285 Restricted cash and cash equivalents 1,264,941 1,503,813 Total cash, cash equivalents and restricted cash presented in the condensed consolidated statements of cash flows $ 1,330,382 $ 1,531,098

SIGNIFICANT ACCOUNTING POLICI27

SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Line Items]
Cash and cash equivalents	$ 65,441		$ 65,441		$ 27,285
Premium deficiency loss	0		0		0
Profit commission reserves	13,900		13,900		11,900
Profit commission expense	3,600	$ 3,000	11,600	$ 5,700
Notes receivable balance related to note placed on non-accrual status	11,700		11,700		14,400
Accrued interest	0		0		100
Deposit Contracts, Assets	13,200		13,200		19,400
Deposit Contracts, Liabilities	46,000		46,000		28,100
Interest Expense, Other	400		500
Interest Income, Other	200		500
Restricted cash and cash equivalents	1,264,941		1,264,941		1,503,813
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 1,330,382	$ 1,394,500	$ 1,330,382	$ 1,394,500	$ 1,531,098	$ 1,242,509

SIGNIFICANT ACCOUNTING POLICI28

SIGNIFICANT ACCOUNTING POLICIES Earnings Per Share Reconciliation (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Weighted average shares outstanding - basic	36,952,472	37,025,703	36,950,828	37,009,539
Effect of dilutive employee and director share-based awards	0	0	0	0
Weighted average shares outstanding - diluted	36,952,472	37,025,703	36,950,828	37,009,539
Stock Options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive stock options outstanding	1,015,627	458,741	1,015,627	358,741
Restricted stock
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Anti-dilutive stock options outstanding	462,787	330,102	462,787	330,102

SIGNIFICANT ACCOUNTING POLICI29

SIGNIFICANT ACCOUNTING POLICIES Income taxes (Details)	6 Months Ended
	Jun. 30, 2018
Verdant
Income Taxes [Line Items]
Income tax rate	21.00%
GRIL | Ireland
Income Taxes [Line Items]
Tax rate on trading income	12.50%
Tax rate on non-trading income	25.00%

FINANCIAL INSTRUMENTS Schedule

FINANCIAL INSTRUMENTS Schedule of Investments Categorized by Level of Fair Value Hierarchy (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 7,841,000	$ 6,861,000	$ 7,841,000	$ 6,861,000	$ 7,020,000	$ 6,988,000	$ 6,780,000	$ 6,763,000
Assets:		877,458,000		877,458,000			1,338,462,000
Debt instruments		13,831,000		13,831,000			7,180,000
Listed equity securities		820,493,000		820,493,000			1,203,672,000
Commodities		36,225,000		36,225,000			121,502,000
Private and unlisted equity securities		6,909,000		6,909,000			6,108,000
Unlisted equity funds measured at net asset value (1)	[1]	26,117,000		26,117,000			24,522,000
Total investments		903,575,000		903,575,000			1,362,984,000
Financial contracts receivable		68,123,000		68,123,000			12,893,000
Listed equity securities, sold not yet purchased		(570,861,000)		(570,861,000)			(812,652,000)
Debt instruments, sold not yet purchased		(110,417,000)		(110,417,000)			(100,145,000)
Total securities sold, not yet purchased		(681,278,000)		(681,278,000)			(912,797,000)
Financial contracts payable		(18,746,000)		(18,746,000)			(22,222,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		800,000	0	800,000	1,750,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net			81,000		116,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0	0	0	1,768,000
Quoted prices in active markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:		846,051,000		846,051,000			1,302,652,000
Debt instruments		0		0			0
Listed equity securities		809,826,000		809,826,000			1,181,150,000
Commodities		36,225,000		36,225,000			121,502,000
Private and unlisted equity securities		0		0			0
Financial contracts receivable		892,000		892,000			22,000
Listed equity securities, sold not yet purchased		(570,861,000)		(570,861,000)			(812,652,000)
Debt instruments, sold not yet purchased		0		0			0
Total securities sold, not yet purchased		(570,861,000)		(570,861,000)			(812,652,000)
Financial contracts payable		(2,504,000)		(2,504,000)			0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3			0		0
Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:		23,566,000		23,566,000			28,822,000
Debt instruments		12,899,000		12,899,000			6,300,000
Listed equity securities		10,667,000		10,667,000			22,522,000
Commodities		0		0			0
Private and unlisted equity securities		0		0			0
Financial contracts receivable		67,231,000		67,231,000			12,871,000
Listed equity securities, sold not yet purchased		0		0			0
Debt instruments, sold not yet purchased		(110,417,000)		(110,417,000)			(100,145,000)
Total securities sold, not yet purchased		(110,417,000)		(110,417,000)			(100,145,000)
Financial contracts payable		(16,242,000)		(16,242,000)			(22,222,000)
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets:		7,841,000		7,841,000			6,988,000
Debt instruments		932,000		932,000			880,000
Listed equity securities		0		0			0
Commodities		0		0			0
Private and unlisted equity securities		6,909,000		6,909,000			6,108,000
Financial contracts receivable		0		0			0
Listed equity securities, sold not yet purchased		0		0			0
Debt instruments, sold not yet purchased		0		0			0
Total securities sold, not yet purchased		0		0			0
Financial contracts payable		0		0			0
Private and unlisted equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		6,909,000	6,085,000	6,909,000	6,085,000	6,135,000	6,108,000	6,076,000	6,109,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		800,000	0	800,000	1,750,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net		(26,000)	9,000	1,000	(6,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0	0	0	1,768,000
Private and unlisted equity securities [Member] | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3				0
Debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		932,000	776,000	932,000	776,000	$ 885,000	$ 880,000	$ 704,000	$ 654,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net		47,000	72,000	52,000	122,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		$ 0	$ 0	$ 0	$ 0
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS Fair Valu

FINANCIAL INSTRUMENTS Fair Value Hierarchy- Additional Information (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		$ 7,841,000	$ 6,861,000	$ 7,841,000	$ 6,861,000	$ 7,020,000	$ 6,988,000	$ 6,780,000	$ 6,763,000
Unlisted equity funds measured at net asset value (1)	[1]	26,117,000		26,117,000			24,522,000
Transfers out of Level 3		0	0	0	(1,768,000)
Transfers from Level 2 to Level 1 due to lock-up period restriction expiration		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net			81,000		116,000
Transfers into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		800,000	0	800,000	1,750,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Quoted prices in active markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers out of Level 3			0		0
Net investment income (loss)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total realized and unrealized gains (losses) and amortization included in earnings, net		0	0	0	0
Change in unrealized gains		0	100,000	100,000	100,000
Debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		932,000	776,000	932,000	776,000	885,000	880,000	704,000	654,000
Transfers out of Level 3		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net		47,000	72,000	52,000	122,000
Transfers into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Private equity and limited partnerships (1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value		6,909,000	6,085,000	6,909,000	6,085,000	$ 6,135,000	$ 6,108,000	$ 6,076,000	$ 6,109,000
Transfers out of Level 3		0	0	0	(1,768,000)
Total realized and unrealized gains (losses) and amortization included in earnings, net		(26,000)	9,000	1,000	(6,000)
Transfers into Level 3		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		800,000	0	800,000	1,750,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances		0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		0	0	0	0
Private equity and limited partnerships (1) | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers out of Level 3				0
Equity Securities [Member] | Quoted prices in active markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers out of Level 3		0		0
Transfers into Level 3		0	0	0	0
Equity Securities [Member] | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers out of Level 3					1,768,000
Financial contracts receivable | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers into Level 3		0	0	0	0
Financial contracts payable
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings		21,000		53,000
Financial contracts payable | Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers into Level 3		$ 0	$ 0	$ 0	$ 0
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS Level 3 r

FINANCIAL INSTRUMENTS Level 3 reconciliation (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unlisted equity funds measured at net asset value (1)	[1]	$ 26,117,000		$ 26,117,000		$ 24,522,000
Beginning balance		7,020,000	$ 6,780,000	6,988,000	$ 6,763,000
Purchases		800,000	0	800,000	1,750,000
Sales		0	0	0	0
Issuances		0	0	0	0
Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net			81,000		116,000
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	(1,768,000)
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount		0	0	0	0
Ending balance		7,841,000	6,861,000	7,841,000	6,861,000
Debt instruments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance		885,000	704,000	880,000	654,000
Purchases		0	0	0	0
Sales		0	0	0	0
Issuances		0	0	0	0
Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net		47,000	72,000	52,000	122,000
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Ending balance		932,000	776,000	932,000	776,000
Private equity and limited partnerships (1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance		6,135,000	6,076,000	6,108,000	6,109,000
Purchases		800,000	0	800,000	1,750,000
Sales		0	0	0	0
Issuances		0	0	0	0
Settlements		0	0	0	0
Total realized and unrealized gains (losses) and amortization included in earnings, net		(26,000)	9,000	1,000	(6,000)
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	(1,768,000)
Ending balance		6,909,000	6,085,000	6,909,000	6,085,000
Financial contracts payable
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total realized and unrealized gains (losses) and amortization included in earnings, net		21,000		53,000
Net investment income (loss)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total realized and unrealized gains (losses) and amortization included in earnings, net		0	0	0	0
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)		0	100,000	100,000	100,000
Quoted prices in active markets (Level 1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers out of Level 3			0		0
Quoted prices in active markets (Level 1) | Total equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0		0
Significant other observable inputs (Level 2) | Private equity and limited partnerships (1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers out of Level 3				0
Significant other observable inputs (Level 2) | Financial contracts receivable
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers into Level 3		0	0	0	0
Significant other observable inputs (Level 2) | Total equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers out of Level 3					1,768,000
Significant other observable inputs (Level 2) | Financial contracts payable
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Transfers into Level 3		$ 0	$ 0	$ 0	$ 0
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS Schedul33

FINANCIAL INSTRUMENTS Schedule of Investments Included in Debt Instruments (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost	$ 12,736	$ 16,448
Debt instruments	13,831	7,180
Corporate debt – U.S.
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost	3,186	8,508
Unrealized gains	0	0
Unrealized losses	(2,170)	(7,186)
Debt instruments	1,016	1,322
Corporate debt – Non U.S.
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost	2,109	2,109
Unrealized gains	0	0
Unrealized losses	(2,099)	(2,057)
Debt instruments	10	52
Municipal debt – U.S.
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost	7,441	5,831
Unrealized gains	5,364	0
Unrealized losses	0	(25)
Debt instruments	12,805	5,806
Total debt instruments
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost	12,736	16,448
Unrealized gains	5,364	0
Unrealized losses	$ (4,269)	$ (9,268)

FINANCIAL INSTRUMENTS Schedul34

FINANCIAL INSTRUMENTS Schedule of Maturity of Debt Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financial Instruments [Abstract]
Debt instruments, trading, within one year, cost	$ 1,551	$ 7,557
Debt instruments, trading, within one year, fair value	234	441
Debt instruments, trading, from one to five years, cost	892	0
Debt instruments, trading, from one to five years, fair value	217	0
Debt instruments, trading, from five to ten years, cost	2,859	2,109
Debt instruments, trading, from five to ten years, fair value	1,324	52
Debt instruments, trading, more than ten years, cost	7,434	6,782
Debt instruments, trading, more than ten years, fair value	12,056	6,687
Cost/ amortized cost	12,736	16,448
Debt instruments	$ 13,831	$ 7,180

FINANCIAL INSTRUMENTS Schedul35

FINANCIAL INSTRUMENTS Schedule of Investments in Equity Securities Trading (Details) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
		Jun. 30, 2018	Dec. 31, 2017
Schedule of Trading Securities and Other Trading Assets [Line Items]
Unlisted equity funds measured at net asset value (1)	[1]	$ 26,117	$ 24,522
Cost/amortized cost		12,736	16,448
Equity securities, trading, at fair value		820,493	1,203,672
Equities – listed
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost		754,110	1,014,426
Unrealized gains		121,165	208,350
Unrealized losses		(54,782)	(19,104)
Equity securities, trading, at fair value		820,493	1,203,672
Total equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost/amortized cost		754,110	1,014,426
Unrealized gains		121,165	208,350
Unrealized losses		$ (54,782)	$ (19,104)
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS Schedul36

FINANCIAL INSTRUMENTS Schedule of Other Investments (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Schedule of Trading Securities and Other Trading Assets [Line Items]
Unlisted equity funds measured at net asset value (1)	[1]	$ 26,117	$ 24,522
Securities Owned Not Readily Marketable		4,000	3,900
Cost		55,296	126,500
Unrealized gains		13,955	25,632
Unrealized losses		0	0
Fair value		69,251	152,132
Equity Funds [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		6,900	6,500
Commodities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost		29,493	101,184
Unrealized gains		6,732	20,318
Unrealized losses		0	0
Fair value		36,225	121,502
Private and unlisted equity securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Cost		25,803	25,316
Unrealized gains		7,223	5,314
Unrealized losses		0	0
Fair value		$ 33,026	$ 30,630
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS NAV Instr

FINANCIAL INSTRUMENTS NAV Instruments (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unlisted equity funds measured at net asset value (1)	[1]	$ 26,117	$ 24,522
Percentage of funds that have investment restrictions		100.00%
Equity Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 6,900	6,500
Estimate of Fair Value Measurement [Member] | Equity Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unlisted equity funds measured at net asset value (1)		$ 26,100	$ 24,500
[1]	Investments measured at fair value using the net asset value practical expedient have not been classified in the fair value hierarchy. The fair value amounts are presented in the above table to facilitate reconciliation to the condensed consolidated balance sheets.

FINANCIAL INSTRUMENTS Investmen

FINANCIAL INSTRUMENTS Investments in Securities Sold, Not Yet Purchased (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Corporate debt – U.S.
Investments Sold, Not yet Purchased [Line Items]
Unrealized gains	$ 0	$ 0
Unrealized losses	(2,170)	(7,186)
Total equity securities
Investments Sold, Not yet Purchased [Line Items]
Unrealized gains	121,165	208,350
Unrealized losses	(54,782)	(19,104)
Securities Sold, Not yet Purchased
Investments Sold, Not yet Purchased [Line Items]
Proceeds	(561,047)	(739,379)
Unrealized gains	6,163	17,541
Unrealized losses	(126,394)	(190,959)
Fair value	(681,278)	(912,797)
Securities Sold, Not yet Purchased | Corporate debt – U.S.
Investments Sold, Not yet Purchased [Line Items]
Proceeds	(8,779)
Unrealized gains	0
Unrealized losses	(279)
Fair value	(9,058)
Securities Sold, Not yet Purchased | Total equity securities
Investments Sold, Not yet Purchased [Line Items]
Proceeds	(456,038)	(643,148)
Unrealized gains	6,163	17,541
Unrealized losses	(120,987)	(187,045)
Fair value	(570,862)	(812,652)
Securities Sold, Not yet Purchased | Sovereign debt – Non U.S.
Investments Sold, Not yet Purchased [Line Items]
Proceeds	(96,230)	(96,231)
Unrealized gains	0	0
Unrealized losses	(5,128)	(3,914)
Fair value	$ (101,358)	$ (100,145)

FINANCIAL INSTRUMENTS Schedul39

FINANCIAL INSTRUMENTS Schedule of Fair Value of Financial Contracts Outstanding (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Financial contracts receivable, at fair value	$ 68,123	$ 12,893
Financial contracts payable	(18,746)	(22,222)
Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, at fair value	68,123	12,893
Financial contracts payable
Derivative [Line Items]
Financial contracts payable	(18,746)	(22,222)
Call options | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	1,783,000	2,656
Financial contracts receivable, at fair value	1,296	91
Commodity Swaps | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	33,924	17,833
Financial contracts receivable, at fair value	1,575	2,142
Commodity Swaps | Financial contracts payable
Derivative [Line Items]
Financial contracts payable, Notional amount of underlying instruments		26,795
Financial contracts payable		(353)
Interest rate swaps | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	21,652	21,269
Financial contracts receivable, at fair value	93	479
Forwards | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments		41,379
Financial contracts receivable, at fair value		801
Forwards | Financial contracts payable
Derivative [Line Items]
Financial contracts payable, Notional amount of underlying instruments	56,810
Financial contracts payable	(1,775)
Futures | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	45,588	5,874
Financial contracts receivable, at fair value	892	12
Futures | Financial contracts payable
Derivative [Line Items]
Financial contracts payable, Notional amount of underlying instruments	69,839
Financial contracts payable	(2,504)
Put options | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	126,059	155
Financial contracts receivable, at fair value	52,946	1
Put options | Financial contracts payable
Derivative [Line Items]
Financial contracts payable, Notional amount of underlying instruments	24,565	130
Financial contracts payable	(13,014)	(14)
Total return swaps – equities | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments	93,762	34,965
Financial contracts receivable, at fair value	11,321	9,357
Total return swaps – equities | Financial contracts payable
Derivative [Line Items]
Financial contracts payable, Notional amount of underlying instruments	17,207	60,663
Financial contracts payable	(1,453)	(21,855)
Warrants and rights on listed equities | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable, Notional amount of underlying instruments		29
Financial contracts receivable, at fair value		10
NO MARKET (E.G. UNLISTED) [Member] | Put options | Financial contracts receivable
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	52,900	0
NO MARKET (E.G. UNLISTED) [Member] | Put options | Financial contracts payable
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	$ 13,000	$ 0

FINANCIAL INSTRUMENTS Schedul40

FINANCIAL INSTRUMENTS Schedule of Reported Gains and Losses on Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	$ (12,250)	$ (19,300)	$ (31,386)	$ (23,261)
Commodity Swaps | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	2,308	(3,746)	4,156	(10,705)
Forwards | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	(2,784)	(289)	(2,907)	334
Futures | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	(6,003)	110	(7,952)	(403)
Interest rate swaps | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	(517)	0	(1,154)	0
Interest Rate Swaps | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	(118)	(198)	(449)	(93)
Options, warrants, and rights | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	(14,929)	(4,584)	(13,842)	(12,112)
Total return swaps – equities | Net investment income (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives recognized in income	$ 9,793	$ (10,593)	$ (9,238)	$ (282)

FINANCIAL INSTRUMENTS Schedul41

FINANCIAL INSTRUMENTS Schedule of Volumes of Derivative Activities (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2018		Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017
Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		$ 914,811		$ 246,455	$ 2,567,530		$ 859,477
Exited		134,641		250,030	469,186		452,990
Forwards | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		9,156		164	63,528		3,640
Exited		14,438		0	47,766		0
Futures
Derivative [Line Items]
Entered				2,890
Exited				5,818
Futures | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		110,201			423,374		32,400
Exited		76,814			312,712		29,887
Interest rate swaps
Derivative [Line Items]
Entered		679,000
Exited	[1]	0
Interest rate swaps | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered					1,783,000
Exited	[1]				0
Options, warrants and rights (1)
Derivative [Line Items]
Entered				229,999
Exited	[1]			0
Options, warrants and rights (1) | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		73,406			245,986		577,917
Exited		9,280	[1]		26,646	[2]	110,102	[1]
Commodity Swaps | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		34,792		2,025	34,792		2,025
Exited		20,948		8,406	49,923		16,588
Total return swaps – equities | Derivatives not designated as hedging instruments (notional amounts)
Derivative [Line Items]
Entered		8,256		11,377	16,850		243,495
Exited		$ 13,161		$ 235,806	$ 32,139		$ 296,413
[1]	Exited amount excludes derivatives which expired or were exercised during the period.
[2]	Exited amount excludes derivatives which expired or were exercised during the period.

FINANCIAL INSTRUMENTS Schedul42

FINANCIAL INSTRUMENTS Schedule of Gross and Net Amounts of Financial Instruments and Cash Collateral (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Financial contracts receivable, Gross amounts of recognized assets	$ 68,123	$ 12,893
Financial contracts receivable, Gross amounts offset in the balance sheet	0	0
Financial contracts receivable	68,123	12,893
Financial contracts receivable, Financial instruments available for offset	(15,359)	(5,128)
Financial contracts receivable, Cash collateral (received) pledged	(22,933)	(1,336)
Financial contracts receivable, Net amount of asset (liability)	29,831	6,429
Financial contracts payable, Gross amounts of recognized assets (liabilities)	(18,746)	(22,222)
Financial contracts payable, Gross amounts offset in the balance sheet	0	0
Financial contracts payable, Net amounts of assets (liabilities) presented in the balance sheet	(18,746)	(22,222)
Financial contracts payable, Financial instruments available for offset	15,359	5,128
Financial contracts payable, Cash collateral (received) pledged	0	17,094
Financial contracts payable, Net amount of asset (liability)	(3,387)	0
Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable	68,123	12,893
Put Option [Member] | Financial contracts receivable
Derivative [Line Items]
Financial contracts receivable	52,946	1
Put Option [Member] | NO MARKET (E.G. UNLISTED) [Member] | Financial contracts receivable
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	$ 52,900	$ 0

DUE TO PRIME BROKERS (Details)

DUE TO PRIME BROKERS (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Due to Prime Brokers [Line Items]
Amounts due to prime brokers	$ 490,172	$ 647,700
Payables to Broker-Dealers and Clearing Organizations	$ 520,172	672,700
GLRE
Due to Prime Brokers [Line Items]
Maximum temporary leverage	30.00%
Maximum long-term leverage	15.00%
GRIL
Due to Prime Brokers [Line Items]
Maximum temporary leverage	20.00%
Maximum long-term leverage	5.00%
Line of Credit [Member]
Due to Prime Brokers [Line Items]
Other Short-term Borrowings	$ 30,000	$ 25,000

LOSS AND LOSS ADJUSTMENT EXPE44

LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Liability for Claims and Claims Adjustment Expense [Line Items]
Case reserves	$ 170,389		$ 178,088
IBNR	303,949		286,292
Gross balance at January 1	464,380	$ 306,641
Less: Losses recoverable	37,005	2,661	29,459	$ 2,704
Net balance at January 1	434,921	303,937
Current year	184,102	203,922
Prior years	(3,463)	6,906
Total incurred	180,639	210,828
Current year	(55,909)	(60,134)
Prior years	(121,609)	(99,763)
Total paid	177,518	159,897
Foreign currency revaluation	709	(1,826)
Net balance at June 30	437,333	356,694
Gross balance at June 30	474,338	359,355
Hurricane [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	(5,800)
Mortgages [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	(3,500)
Homeowners' property contracts [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	(3,500)	6,900
Non standard Automobile Business [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	3,400
Professional Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	3,200
General Liability
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	1,900
Surety Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	(1,200)
Accident & Health
Liability for Claims and Claims Adjustment Expense [Line Items]
Gross balance at January 1	22,181	18,993
Less: Losses recoverable	0	0	$ 0	$ 0
Net balance at January 1	22,181	18,993
Current year	27,046	21,674
Prior years	765	384
Total incurred	27,811	21,290
Current year	(8,740)	(7,704)
Prior years	(16,564)	(14,637)
Total paid	25,304	22,341
Foreign currency revaluation	0	0
Net balance at June 30	24,688	17,942
Gross balance at June 30	24,688	$ 17,942
Other Specialty
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Period Increase (Decrease)	$ (400)

RETROCESSION (Details)

RETROCESSION (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Ceded Credit Risk [Line Items]
Loss and loss adjustment expenses incurred, net	$ 84,815,000	$ 106,016,000	$ 180,639,000	$ 210,828,000
Loss and loss expenses recovered and recoverable	15,300,000	(200,000)	34,700,000	(100,000)
Loss and loss adjustment expenses recoverable	37,005,000	$ 2,661,000	37,005,000	$ 2,661,000	$ 29,459,000	$ 2,704,000
Funds withheld	16,946,000		16,946,000		23,579,000
Collateral Held in Trust	380,900,000		380,900,000		377,900,000
Provision for uncollectible losses recoverable	0		0		0
Unrated [Member]
Ceded Credit Risk [Line Items]
Loss and loss adjustment expenses recoverable	31,000,000		31,000,000		26,300,000
AM Best, A- Rating [Member]
Ceded Credit Risk [Line Items]
Loss and loss adjustment expenses recoverable	$ 6,000,000		$ 6,000,000		$ 3,100,000

SHARE-BASED COMPENSATION Narrat

SHARE-BASED COMPENSATION Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares	0	71,335
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0
Number of stock options exercised	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value	$ 10.51
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 2.5	$ 1.9
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued from the exercise of stock options	0
Stock options | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for stock incentive plan	5,000,000		5,000,000
Shares available for future issuance relating to share purchase options granted to service provider	1,011,840		1,271,154
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Number of RSUs issued to employees	245,975
Stock Granted, Value, Share-based Compensation, Forfeited	$ 0.1	$ 0
Restricted stock | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	191,255	113,955
Number of restricted shares forfeited	14,314	46,319
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years 6 months
Performance Shares [Member] | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	30,660
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock compensation expense reversed due to forfeitures		$ 0
Number of RSUs issued to employees	28,301	11,559
Director [Member] | Restricted stock | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	54,720	37,840
Chief Executive Officer [Member] | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0
Former Chief Executive Officer [Member] | Restricted stock | Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Granted, Value, Share-based Compensation, Forfeited		$ 0

SHARE-BASED COMPENSATION Restri

SHARE-BASED COMPENSATION Restricted Shares (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of non-vested restricted shares, Balance	22,798
Number of non-vested restricted shares, Granted	28,301	11,559
Number of non-vested restricted shares, Vested	(4,053)
Number of non-vested restricted shares, Forfeited	(648)	0
Number of non-vested restricted shares, Balance	46,398
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, Balance	$ 23.50
Weighted average grant date fair value, Granted	15.90
Weighted average grant date fair value, Vested	32.21
Weighted average grant date fair value, Forfeited	21.65
Weighted average grant date fair value, Balance	$ 18.13
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of non-vested restricted shares, Balance	331,510
Number of non-vested restricted shares, Granted	245,975
Number of non-vested restricted shares, Vested	(100,384)
Number of non-vested restricted shares, Forfeited	(14,314)
Number of non-vested restricted shares, Balance	462,787
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, Balance	$ 23.45
Weighted average grant date fair value, Granted	15.78
Weighted average grant date fair value, Vested	27.74
Weighted average grant date fair value, Forfeited	21.61
Weighted average grant date fair value, Balance	$ 18.50
Stock Granted, Value, Share-based Compensation, Forfeited	$ 0.1	$ 0
Common Class A [Member] | Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	191,255	113,955
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Number of restricted shares forfeited	(14,314)	(46,319)
Common Class A [Member] | Director [Member] | Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	54,720	37,840

SHARE-BASED COMPENSATION Rest48

SHARE-BASED COMPENSATION Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of non-vested restricted shares, Balance	331,510
Number of non-vested restricted shares, Granted	245,975
Number of non-vested restricted shares, Vested	(100,384)
Number of non-vested restricted shares, Forfeited	(14,314)
Number of non-vested restricted shares, Balance	462,787
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, Balance	$ 23.45
Weighted average grant date fair value, Granted	15.78
Weighted average grant date fair value, Vested	27.74
Weighted average grant date fair value, Forfeited	21.61
Weighted average grant date fair value, Balance	$ 18.50
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of non-vested restricted shares, Balance	22,798
Number of non-vested restricted shares, Granted	28,301	11,559
Number of non-vested restricted shares, Vested	(4,053)
Number of non-vested restricted shares, Forfeited	(648)	0
Number of non-vested restricted shares, Balance	46,398
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, Balance	$ 23.50
Weighted average grant date fair value, Granted	15.90
Weighted average grant date fair value, Vested	32.21
Weighted average grant date fair value, Forfeited	21.65
Weighted average grant date fair value, Balance	$ 18.13
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures		$ 0

SHARE-BASED COMPENSATION Share

SHARE-BASED COMPENSATION Share Based Compensation Options Rollfoward (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value	$ 10.51
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	6 years 5 months	6 years 11 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of options, Balance	1,015,627
Number of options, Granted	0
Number of options, Exercised	0
Number of options, Forfeited	0
Number of options, Expired	0
Number of options, Balance	1,015,627	1,015,627
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, Balance	$ 23.55
Weighted average exercise price, Granted	0
Weighted average exercise price, Exercised	0
Weighted average exercise price, Forfeited	0
Weighted average exercise price, Expired	0
Weighted average exercise price, Balance	23.55	$ 23.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average grant date fair value, Balance	9.89
Weighted average grant date fair value, Granted	0
Weighted average grant date fair value, Exercised	0
Weighted average grant date fair value, Forfeited	0
Weighted average grant date fair value, Expired	0
Weighted average grant date fair value, Balance	$ 9.89	$ 9.89

SHARE-BASED COMPENSATION Black

SHARE-BASED COMPENSATION Black Scholes option pricing model assumptions (Details)	6 Months Ended
	Jun. 30, 2018shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($)		3 Months Ended			6 Months Ended
		Jun. 30, 2018		Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Investment Income		$ 40,656,000		$ 39,149,000	$ 185,872,000		$ 27,531,000
Debt instruments		13,831,000			13,831,000			$ 7,180,000
Listed equity securities		820,493,000			$ 820,493,000			1,203,672,000
Investment Advisory Agreement | Board of Directors Chairman
Related Party Transaction [Line Items]
Performance compensation full rate					20.00%
Performance compensation reduced rate					10.00%
Loss carry forward recoupment required					150.00%
Performance compensation expense		0		(1,200,000)	$ 0		0
Investment management fee rate - monthly					0.125%
Investment management fee rate - annual					1.50%
Management fees		4,100,000		$ 4,300,000	$ 8,600,000		$ 8,600,000
Equity Securities [Member] | Board of Directors Chairman
Related Party Transaction [Line Items]
Listed equity securities		34,000,000			34,000,000			39,200,000
Service Agreement [Member] | Board of Directors Chairman
Related Party Transaction [Line Items]
Investor relations monthly fee					5,000
Private Equity Funds [Member]
Related Party Transaction [Line Items]
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months		6,950,000	[1]		6,950,000	[1]		$ 6,500,000
Unrecorded Unconditional Purchase Obligation, Due within Two Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Three Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Four Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due after Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation	[1]	$ 6,950,000			$ 6,950,000
[1]	Given the nature of these investments, the Company is unable to determine with any degree of accuracy when these commitments will be called. Therefore, for purposes of the above table, the Company has assumed that all commitments with no fixed payment schedules will be called during the year ending December 31, 2018

RELATED PARTY TRANSACTIONS No52

RELATED PARTY TRANSACTIONS Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Noncontrolling Interest [Line Items]
Redeemable non-controlling interest in related party joint venture	$ 6,436	$ 5,367	$ 6,436	$ 5,367	$ 7,169	$ 5,884
Nonredeemable Noncontrolling Interest	10,719	11,780	10,719	11,780	12,933	11,561
Noncontrolling Interest in Joint Ventures	17,155	17,147	17,155	17,147	20,102	$ 17,445
Non-controlling interest in related party joint venture	10,719		10,719		$ 12,933
Change in capital account allocation of non-controlling interest in related party joint venture	$ (621)	$ (550)	(2,947)	(298)
Net Income (Loss) Attributable to Noncontrolling Interest			(2,947)	(298)
Change in non-controlling interest in related party joint venture			(2,214)	219
Non-controlling interest in joint venture
Noncontrolling Interest [Line Items]
Temporary Equity, Net Income			(1,079)	(97)
Temporary Equity, Carrying Amount, Period Increase (Decrease)			(346)	420
Change in non-controlling interest in related party joint venture			(2,214)	219
Nonredeemable Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Change in capital account allocation of non-controlling interest in related party joint venture			(1,868)	(201)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders			346	(420)
Non-controlling interest in joint venture
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders			$ 0	$ 0

COMMITMENTS AND CONTINGENCIES53

COMMITMENTS AND CONTINGENCIES (Details) - USD ($)	6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Mar. 28, 2018
Letters of Credit Facilities [Line Items]
Contractual Obligation, Future Minimum Payments Due, Remainder of Fiscal Year	$ 7,036,000
Amount of letters of credit issued	192,500,000		$ 188,500,000
Total equity securities, restricted cash, and cash and cash equivalents fair value pledged as security against the letters of credit	198,700,000		200,400,000
Facility
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	450,000,000
Facility | Butterfield Bank (Cayman) Limited [Member]
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 50,000,000			$ 100,000,000
Notice period required for termination	90 days
Facility | Citibank Europe plc
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 400,000,000
Notice period required for termination	120 days
Facility | JP Morgan Chase Bank N.A.
Letters of Credit Facilities [Line Items]
Notice period required for termination	120 days
Revolving Credit Facility [Member] | Bank of Nova Scotia [Member]
Letters of Credit Facilities [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 50,000,000
Line of Credit, Current	$ 30,000,000		$ 25,000,000
Line of Credit Facility, Interest Rate at Period End	3.11%		2.47%
Line of Credit Facility, Collateral	36,225		37,700
Interest Expense	$ 400,000	$ 0

COMMITMENTS AND CONTINGENCIES L

COMMITMENTS AND CONTINGENCIES Lease (Details) $ in Thousands, € in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2018USD ($)		Jun. 30, 2017USD ($)	Jun. 30, 2018USD ($)		Jun. 30, 2018EUR (€)	Dec. 31, 2017USD ($)
Operating Leased Assets [Line Items]
Total rent expense related to leased office space		$ 200		$ 200
Operating Lease obligations, 2018		86			$ 86
Operating lease obligations, 2019		172			172
Operating lease obligations, 2020		172			172
Operating lease obligations, 2021		64			64
Operating lease obligations, 2022		0			0
Operating lease obligations, Thereafter		0			0
Operating lease obligations, Total		494			494
Contractual Obligations Total 2018		7,036			7,036
Contractual Obligations Total 2019		172			172
Contractual Obligations Total 2020		172			172
Contractual Obligations Total 2021		64			64
Contractual Obligations Total 2022		0			0
Contractual Obligations Total, Thereafter		0			0
Contractual Obligations Total		7,444			$ 7,444
GLRE
Operating Leased Assets [Line Items]
Operating lease renewal option					5 years		5 years
GLRE | Minimum
Operating Leased Assets [Line Items]
Annual rent payments					$ 300
GLRE | Maximum
Operating Leased Assets [Line Items]
Annual rent payments					500
GRIL
Operating Leased Assets [Line Items]
Annual rent payments | €							€ 0.1
Private equity and limited partnerships (1)
Operating Leased Assets [Line Items]
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months		6,950	[1]		6,950	[1]		$ 6,500
Unrecorded Unconditional Purchase Obligation, Due within Two Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Three Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Four Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation, Due after Five Years	[1]	0			0
Unrecorded Unconditional Purchase Obligation	[1]	$ 6,950			$ 6,950
[1]	Given the nature of these investments, the Company is unable to determine with any degree of accuracy when these commitments will be called. Therefore, for purposes of the above table, the Company has assumed that all commitments with no fixed payment schedules will be called during the year ending December 31, 2018

SEGMENT REPORTING (Details)

SEGMENT REPORTING (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Number of operating segments				1
Gross premiums written		$ 142,109	$ 174,889	$ 317,234	$ 372,103
Premiums Written, Gross as a percentage of Total Gross Premiums Written		100.00%	100.00%	100.00%	100.00%
Total Property
Segment Reporting Information [Line Items]
Gross premiums written		$ 26,344	$ 36,815	$ 53,849	$ 76,772
Premiums Written, Gross as a percentage of Total Gross Premiums Written		18.50%	21.00%	17.00%	20.60%
Commercial
Segment Reporting Information [Line Items]
Gross premiums written		$ 3,069	$ 2,102	$ 5,712	$ 5,481
Premiums Written, Gross as a percentage of Total Gross Premiums Written		2.20%	1.20%	1.80%	1.50%
Motor
Segment Reporting Information [Line Items]
Gross premiums written		$ 18,391	$ 14,200	$ 40,813	$ 29,509
Premiums Written, Gross as a percentage of Total Gross Premiums Written		12.90%	8.10%	12.90%	7.90%
Personal
Segment Reporting Information [Line Items]
Gross premiums written		$ 4,884	$ 20,513	$ 7,324	$ 41,782
Premiums Written, Gross as a percentage of Total Gross Premiums Written		3.40%	11.70%	2.30%	11.20%
Total Casualty
Segment Reporting Information [Line Items]
Gross premiums written		$ 98,440	$ 114,361	$ 204,247	$ 235,829
Premiums Written, Gross as a percentage of Total Gross Premiums Written		69.30%	65.40%	64.40%	63.40%
General Liability
Segment Reporting Information [Line Items]
Gross premiums written		$ 137	$ 401	$ 1,370	$ 2,191
Premiums Written, Gross as a percentage of Total Gross Premiums Written		0.10%	0.20%	0.40%	0.60%
Motor Liability
Segment Reporting Information [Line Items]
Gross premiums written		$ 72,118	$ 75,883	$ 155,680	$ 152,836
Premiums Written, Gross as a percentage of Total Gross Premiums Written		50.70%	43.40%	49.10%	41.10%
Professional Liability
Segment Reporting Information [Line Items]
Gross premiums written		$ 673	$ 2,168	$ 1,111	$ 6,221
Premiums Written, Gross as a percentage of Total Gross Premiums Written		0.50%	1.20%	0.40%	1.70%
Workers' Compensation
Segment Reporting Information [Line Items]
Gross premiums written		$ 3,135	$ 1,996	$ 6,694	$ 7,418
Premiums Written, Gross as a percentage of Total Gross Premiums Written		2.20%	1.20%	2.10%	2.00%
Multi-line
Segment Reporting Information [Line Items]
Gross premiums written	[1]	$ 22,377	$ 33,913	$ 39,392	$ 67,163
Premiums Written, Gross as a percentage of Total Gross Premiums Written	[1]	15.80%	19.40%	12.40%	18.00%
Total Other
Segment Reporting Information [Line Items]
Gross premiums written		$ 17,325	$ 23,713	$ 59,138	$ 59,502
Premiums Written, Gross as a percentage of Total Gross Premiums Written		12.20%	13.60%	18.60%	16.00%
Accident & Health
Segment Reporting Information [Line Items]
Gross premiums written		$ 12,667	$ 10,406	$ 42,244	$ 33,510
Premiums Written, Gross as a percentage of Total Gross Premiums Written		8.90%	6.00%	13.30%	9.00%
Financial
Segment Reporting Information [Line Items]
Gross premiums written		$ 3,813	$ 12,931	$ 15,027	$ 24,860
Premiums Written, Gross as a percentage of Total Gross Premiums Written		2.70%	7.40%	4.70%	6.70%
Marine
Segment Reporting Information [Line Items]
Gross premiums written		$ 0	$ 0	$ 371	$ 0
Premiums Written, Gross as a percentage of Total Gross Premiums Written		0.00%	0.00%	0.10%	0.00%
Other Specialty
Segment Reporting Information [Line Items]
Gross premiums written		$ 845	$ 376	$ 1,496	$ 1,132
Premiums Written, Gross as a percentage of Total Gross Premiums Written		0.60%	0.20%	0.50%	0.30%
[1]	Contracts that cover more than one line of business are grouped as “multi-line” regardless of whether a portion of the underlying business is covered by one of the lines of business listed above. The Company’s multi-line business predominantly relates to casualty reinsurance. The prior period comparative information has been reclassified to conform to the current period presentation.

SEGMENT REPORTING Geographic in

SEGMENT REPORTING Geographic information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017
Revenue from External Customer [Line Items]
Gross premiums written		$ (142,109)	$ (174,889)	$ (317,234)		$ (372,103)
Gross premiums by geographical area as a percentage of total gross premiums		100.00%	100.00%	100.00%		100.00%
U.S. and Caribbean
Revenue from External Customer [Line Items]
Gross premiums written		$ (127,475)	$ (152,014)	$ (285,182)		$ (323,772)
Gross premiums by geographical area as a percentage of total gross premiums		89.70%	86.90%	89.90%		87.00%
Worldwide (1)
Revenue from External Customer [Line Items]
Gross premiums written	[1]	$ (14,603)	$ (22,784)	$ (31,881)		$ (48,078)
Gross premiums by geographical area as a percentage of total gross premiums	[1]	10.30%	13.00%	10.00%		12.90%
Europe
Revenue from External Customer [Line Items]
Gross premiums written		$ (31)	$ (91)	$ (217)		$ (237)
Gross premiums by geographical area as a percentage of total gross premiums		0.00%	0.10%	0.10%		0.10%
Asia (2)
Revenue from External Customer [Line Items]
Gross premiums written		$ 0	$ 0	$ 46	[2]	$ (16)
Gross premiums by geographical area as a percentage of total gross premiums		0.00%	0.00%	0.00%	[2]	0.00%
[1]	“Worldwide” is comprised of contracts that reinsure risks in more than one geographic area and do not specifically exclude the U.S.
[2]	The negative balance represents reversal of premiums due to premium adjustments, termination of contracts or premium returned upon novation or commutation of contracts.