Restructuring Expenses (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Activity in restructuring liability account
Beginning Balance	$ 1,665
Provision	238	3,184
Usage	(1,895)	(1,523)
Reclass		4
Ending Balance	8	1,665
One-time employee termination benefits [Member]
Activity in restructuring liability account
Beginning Balance	1,101
Provision	145	2,230
Usage	(1,238)	(1,129)
Reclass
Ending Balance	8	1,101
Lease/rental terminations [Member]
Activity in restructuring liability account
Beginning Balance	448
Provision	(12)	558
Usage	(436)	(110)
Reclass
Ending Balance		448
Relocation, move, other expenses [Member]
Activity in restructuring liability account
Beginning Balance	116
Provision	105	396
Usage	(221)	(284)
Reclass		4
Ending Balance		$ 116