Segment Information (Details 2) (Medicare)	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Medicare
Revenues by major customer
Revenues from major customers as a percentage of product revenues	22.00%	20.00%	23.00%	21.00%

Percentage of revenue generated from a single external customer that accounts for 10 percent or more of an entity's revenues.

No definition available.

Name:	us-gaap_EntityWideRevenueMajorCustomerPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration