Subsequent Events (Details) (Subsequent event, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Subsequent event
Subsequent events
Employee termination benefits and other related costs	$ 1,100

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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+ Details