BUSINESS COMBINATIONS (2013 Acquisitions) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 13, 2013
Summary of recognized assets acquired and liabilities assumed
Goodwill	$ 452,669	$ 570,960	$ 579,715
Evergreen Oil, Inc.
Summary of recognized assets acquired and liabilities assumed
Inventories and supplies				1,089
Prepaid and other current assets				1,018
Property, plant and equipment				40,563
Permits and other intangibles				17,100
Deferred tax assets, less current portion				0
Other assets				3,368
Current liabilities				(6,750)
Closure and post-closure liabilities				(659)
Remedial liabilities, less current portion				(1,640)
Other long-term liabilities				(2,059)
Total identifiable net assets				52,030
Goodwill				4,288
Total				56,318
Evergreen Oil, Inc. | Preliminary Allocations
Summary of recognized assets acquired and liabilities assumed
Inventories and supplies				1,089
Prepaid and other current assets				1,291
Property, plant and equipment				40,563
Permits and other intangibles				17,100
Deferred tax assets, less current portion				2,368
Other assets				3,607
Current liabilities				(6,198)
Closure and post-closure liabilities				(659)
Remedial liabilities, less current portion				(2,103)
Other long-term liabilities				(1,139)
Total identifiable net assets				55,919
Goodwill				0
Total				55,919
Evergreen Oil, Inc. | Measurement Period Adjustments
Summary of recognized assets acquired and liabilities assumed
Inventories and supplies				0
Prepaid and other current assets				(273)
Property, plant and equipment				0
Permits and other intangibles				0
Deferred tax assets, less current portion				(2,368)
Other assets				(239)
Current liabilities				(552)
Closure and post-closure liabilities				0
Remedial liabilities, less current portion				463
Other long-term liabilities				(920)
Total identifiable net assets				(3,889)
Goodwill				4,288
Total				$ 399