Acquisitions (Details)	0 Months Ended	12 Months Ended
	Jan. 31, 2012 Hospital	Dec. 31, 2014 Hospital	Dec. 31, 2013 Hospital	Dec. 31, 2012 Hospital
Summary of acquisitions of animal hospitals and laboratories
Acquisitions relocated into our existing animal hospitals		(4)	(2)	(6)
Sold, closed or merged		(9)	(18)	(6)
Net increase		34	0	68
Net increase		3	1	2
Acquisitions, excluding AVC [Member]
Summary of acquisitions of animal hospitals and laboratories
Acquisitions, excluding AVC		47	20	35
AVC [Member]
Summary of acquisitions of animal hospitals and laboratories
Acquisitions, excluding AVC	44	0	0	44
Animal Hospital [Member]
Summary of acquisitions of animal hospitals and laboratories
New facilities		0	0	1
Acquisitions [Member]
Summary of acquisitions of animal hospitals and laboratories
Acquisitions, excluding AVC		0	1	1
Acquisitions relocated into our existing laboratories [Member]
Summary of acquisitions of animal hospitals and laboratories
Acquisitions relocated into our existing laboratories		0	0	(1)
New facilities [Member]
Summary of acquisitions of animal hospitals and laboratories
New facilities		3	0	2