Allowance Accounts (Schedule Of Allowance Accounts) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts receivable - Trade, net of allowance for uncollectible accounts of $4,445 and $4,527, respectively	$ 5,152,000		$ 4,000,000
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Deductions					4,000,000
Remaining trade receivable write off					4,000,000
Allowance for Doubtful Accounts [Member] | Helix [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance, Beginning Balance	4,000,000		4,460,000		5,105,000
Valuation Allowances and Reserves, Deductions	1,257,000	[1]	61,000	[2]	4,108,000	[3]
Valuation Allowances and Reserves, Recoveries	(105,000)		(521,000)		(4,753,000)	[4]
Valuation Allowances and Reserves, Balance, Ending Balance	5,152,000		4,000,000		4,460,000
Valuation Allowance of Deferred Tax Assets [Member] | Helix [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance, Beginning Balance	14,310,000		8,497,000
Valuation Allowances and Reserves, Deductions	2,081,000	[1]	5,813,000	[2]	8,497,000	[3]
Valuation Allowances and Reserves, Balance, Ending Balance	16,391,000		14,310,000		8,497,000
WOSEA [Member] | Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Remaining trade receivable write off					3,700,000
WOSEA [Member] | Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Deductions	2,000,000		4,900,000		7,300,000
Oil And Gas Operations In United Kingdom [Member] | Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Deductions	$ 100,000		$ 900,000

[1] The increase in valuation allowance includes $2.0 million related to our WOSEA operations and $0.1 million to our oil and gas operations in the United Kingdom. WOSEA has a full valuation allowance against its deferred tax asset balance.

[2] The increase in valuation allowance includes $4.9 million related to our WOSEA and $0.9 million to our oil and gas operations in the United Kingdom.

[3] Amounts include a $4.0 million bad debt allowance related to a large international construction contract and a $7.3 million increase in valuation allowance related to our WOSEA operations with the remaining allowance being related to our acquisition of the remaining 50% of the Camelot field in the United Kingdom.

[4] Includes the $3.7 million of bad debt expense related to settlement of third party claims related to a terminated international construction contract in Australia (Note 13).