Goodwill (Details Textual) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012 Segment	Jun. 30, 2011
Goodwill (Textual)
Goodwill impairment charges	$ 0	$ 0
Number of reportable segments	4

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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+ Details