Selected Asset Information (Details 2) (USD $)	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Intangible assets:
Gross Carrying Value		$ 6,200,000		$ 6,200,000
Accumulated Amortization		(5,819,000)		(5,723,000)
Total Net Book Value		381,000		477,000
Other:
Cost method investments		7,123,000		6,713,000
Indemnification receivable from PGS and other assets		1,436,000		1,447,000
Total other		8,559,000		8,160,000
Total other assets, net		8,940,000		8,637,000
Amortization expense	600,000	100,000	1,800,000
Order backlog
Intangible assets:
Gross Carrying Value		5,700,000		5,700,000
Accumulated Amortization		(5,700,000)		(5,629,000)
Total Net Book Value				71,000
License agreement
Intangible assets:
Gross Carrying Value		500,000		500,000
Accumulated Amortization		(119,000)		(94,000)
Total Net Book Value		$ 381,000		$ 406,000