Committments and Contingencies (Details) (USD $) In Millions	Jun. 30, 2011	Sep. 30, 2008
Committments [Abstract]
Period end lease indemnifications	$ 650
Recorded liability for lease indemnifications	200
Earnout Payment Of Business Acquisition		$ 150

Name:

via_IndemnificationObligationsOfDiscontinuedBusinesses

Namespace Prefix:

via

Data Type:

xbrli:monetaryItemType

Balance Type:

credit

Period Type:

instant