Summary Of Significant Accounting Policies (Changes in the Carrying Amount of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Goodwill [Roll Forward]
Goodwill	$ 44,840	$ 44,840
Accumulated impairment losses	(44,840)	(44,840)	(40,700)
Goodwill acquired during the year	0	0
Impairment losses	0	(4,140)	0
Goodwill	44,840	44,840	44,840
Goodwill, net of accumulated impairment losses	0	0
Storage Systems [Member]
Goodwill [Roll Forward]
Goodwill	40,700	40,700
Accumulated impairment losses	(40,700)	(40,700)	(40,700)
Goodwill acquired during the year	0	0
Impairment losses	0	0
Goodwill	40,700	40,700
Goodwill, net of accumulated impairment losses	0	0
Standalone Storage Software [Member]
Goodwill [Roll Forward]
Goodwill	4,140	4,140
Accumulated impairment losses	(4,140)	(4,140)	0
Goodwill acquired during the year	0	0
Impairment losses	0	(4,140)
Goodwill	4,140	4,140
Goodwill, net of accumulated impairment losses	$ 0	$ 0