CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
CURRENT ASSETS
Cash and cash equivalents	$ 9,772	$ 13,233
Accounts receivable	68,181	41,246
Commodity derivative assets	0	48,260
Prepaid expenses and other current assets	1,036	856
TOTAL CURRENT ASSETS	78,989	103,595
PROPERTY AND EQUIPMENT
Oil and natural gas properties, at cost, using the successful efforts method of accounting, includes unproved properties of $605,736 and $524,563 at December 31, 2016 and 2015, respectively	2,697,073	2,482,211
Accumulated depreciation, depletion, amortization, and impairment	(1,652,930)	(1,543,796)
Oil and natural gas properties, net	1,044,143	938,415
Other property and equipment, net of accumulated depreciation of $14,327 and $14,660 at December 31, 2016 and 2015, respectively	528	179
NET PROPERTY AND EQUIPMENT	1,044,671	938,594
DEFERRED CHARGES AND OTHER LONG-TERM ASSETS	5,167	19,247
TOTAL ASSETS	1,128,827	1,061,436
CURRENT LIABILITIES
Accounts payable	4,142	5,036
Accrued liabilities	50,952	58,003
Commodity derivative liabilities	16,237	0
TOTAL CURRENT LIABILITIES	71,331	63,039
LONG-TERM LIABILITIES
Credit facility	316,000	66,000
Accrued incentive compensation	1,485	7,902
Commodity derivative liabilities	482	0
Deferred revenue	518	3,257
Asset retirement obligations	13,350	10,585
TOTAL LIABILITIES	403,166	150,783
COMMITMENTS AND CONTINGENCIES (Note 12)
MEZZANINE EQUITY
Partners' equity - redeemable preferred units, 53 and 77 units outstanding at December 31, 2016 and 2015, respectively	54,015	79,162
EQUITY
Partners' equity - general partner interest	0	0
Noncontrolling interests	1,021	1,144
TOTAL EQUITY	671,646	831,491
TOTAL LIABILITIES, MEZZANINE EQUITY AND EQUITY	1,128,827	1,061,436
Common Units
EQUITY
Partners' equity - units	489,023	574,648
Subordinated Units
EQUITY
Partners' equity - units	$ 181,602	$ 255,699

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.