Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable, allowance for doubtful accounts	$ 154	$ 223
Depreciation expense	1,921	1,994	2,127
Interest expense	136	142	135
Amortization expense	229	264	262
Options maximum term		5 years	5 years
Research and development	4,694	4,876	4,485
Global Coils [Member]
Summary Of Significant Accounting Policies [Line Items]
Ownership interest in joint venture	50.00%
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Vesting period of options under equity incentive plan	3 years
Options maximum term	6 years
Maximum [Member] | Building and Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	40 years
Maximum [Member] | Machinery and Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	12 years
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Vesting period of options under equity incentive plan	1 year
Options maximum term	5 years
Minimum [Member] | Building and Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	5 years
Minimum [Member] | Machinery and Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life	3 years
Customer Funded Tooling Costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Research and development	$ 336	$ 266	$ 35