Sch1-STATEMENT OF CASH FLOWS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Cash Provided by (Used in) Operating Activities	$ 55,413	$ (42,684)	$ 68,574
Change in restricted cash	8,396	19,143	13,060
Loans from (to) associated companies	0fro_LoanAdvancedToAssociateCompanies	250fro_LoanAdvancedToAssociateCompanies	(250)fro_LoanAdvancedToAssociateCompanies
Investment in associated companies	0	(6,001)	(13,298)
Proceeds from sale of investment in associated companies	0	242	0
Proceeds from Noncontrolling Interests	49	0	0
Net Cash Provided by (Used in) Investing Activities	19,735	13,286	(2,993)
Net proceeds from issuance of shares	52,934	4,802	0
Repayments of long-term debt, convertible bond buy backs and cash payments of debt conversion	(90,612)us-gaap_RepaymentsOfLongTermDebt	(23,781)us-gaap_RepaymentsOfLongTermDebt	(24,921)us-gaap_RepaymentsOfLongTermDebt
Repayments of Related Party Debt	(6,103)us-gaap_RepaymentsOfRelatedPartyDebt	(402)us-gaap_RepaymentsOfRelatedPartyDebt	0us-gaap_RepaymentsOfRelatedPartyDebt
Net cash used in financing activities	(64,827)	(54,446)	(88,544)
Cash and Cash Equivalents, Period Increase (Decrease)	10,321	(83,844)	(22,963)
Cash and cash equivalents at beginning of year	53,759	137,603	160,566
Cash and cash equivalents at end of year	64,080	53,759	137,603
Interest paid, net of interest capitalized	76,614us-gaap_InterestPaidNet	91,120us-gaap_InterestPaidNet	98,991us-gaap_InterestPaidNet
Income taxes paid	370us-gaap_IncomeTaxesPaid	493us-gaap_IncomeTaxesPaid	518us-gaap_IncomeTaxesPaid
Parent [Member]
Net Cash Provided by (Used in) Operating Activities	(17,185)	(19,497)	(39,682)
Change in restricted cash	1,283	(1,578)	0
Loans from (to) associated companies	0	250	(250)
Investment in associated companies	0	(6,001)	(13,298)
Proceeds from sale of investment in associated companies	0	242	0
Proceeds from Noncontrolling Interests	49	0	0
Net Cash Provided by (Used in) Investing Activities	1,332	(7,087)	(13,548)
Net proceeds from issuance of shares	52,934	4,802	0
Repayments of long-term debt, convertible bond buy backs and cash payments of debt conversion	(35,877)	(2,250)	0
Repayments of Related Party Debt	(6,103)
Net cash used in financing activities	10,954	2,552	0
Cash and Cash Equivalents, Period Increase (Decrease)	(4,899)	(24,032)	(53,230)
Cash and cash equivalents at beginning of year	6,568	30,600	83,830
Cash and cash equivalents at end of year	1,669	6,568	30,600
Interest paid, net of interest capitalized	15,124	10,125	10,125
Income taxes paid	$ 0	$ 0	$ 0

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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The cash inflow from the additional capital contribution to the entity.

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Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

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