Relocation And Severance Plan (Expenses Incurred Under The Relocation And Severance Plan By Reporting Segment) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Number of employees relocated	21
Construction And Installation [Member] | Relocation Costs [Member]
Costs incurred or charged to expense	$ 95	$ 616
Total cost incurred	711
Other Offshore Services [Member] | Relocation Costs [Member]
Costs incurred or charged to expense	0	24
Total cost incurred	24
Corporate [Member] | Relocation Costs [Member]
Costs incurred or charged to expense	25	308
Total cost incurred	333
Relocation Costs [Member]
Costs incurred or charged to expense	120	948
Total cost incurred	1,068
Construction And Installation [Member] | One-time Termination Benefits [Member]
Costs incurred or charged to expense	(1)	23
Total cost incurred	22
Other Offshore Services [Member] | One-time Termination Benefits [Member]
Costs incurred or charged to expense	0	0
Total cost incurred	0
Corporate [Member] | One-time Termination Benefits [Member]
Costs incurred or charged to expense	0	8
Total cost incurred	8
One-time Termination Benefits [Member]
Costs incurred or charged to expense	(1)	31
Total cost incurred	$ 30