FRESH START ACCOUNTING - Liabilities Subject to Compromise (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Feb. 28, 2017	Oct. 20, 2016
Fresh-Start Adjustment [Line Items]
Liabilities subject to compromise	$ 0
Revaluation of Liabilities
Fresh-Start Adjustment [Line Items]
Accrued interest		$ 35,182
Liabilities subject to compromise		1,110,182
Cash payment to senior noteholders		(100,000)
Issuance of 2022 Second Lien Notes to former holders of the senior notes		(225,000)
Gain on settlement of liabilities subject to compromise		230,445
Common Stock | Revaluation of Liabilities
Fresh-Start Adjustment [Line Items]
Equity fair value adjustments		(539,089)
Warrant
Fresh-Start Adjustment [Line Items]
Equity fair value adjustments		$ (15,648)
Convertible Debt | Notes Due Two Thousand Seventeen
Fresh-Start Adjustment [Line Items]
Interest rate		1.75%
Convertible Debt | Notes Due Two Thousand Seventeen | Revaluation of Liabilities
Fresh-Start Adjustment [Line Items]
Liabilities subject to compromise		$ 300,000
Senior Notes | Notes Due Two Thousand Twenty Two
Fresh-Start Adjustment [Line Items]
Interest rate		7.50%	7.50%
Senior Notes | Notes Due Two Thousand Twenty Two | Revaluation of Liabilities
Fresh-Start Adjustment [Line Items]
Liabilities subject to compromise		$ 775,000