Segments (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Oct. 02, 2011	Sep. 30, 2012 Segment	Oct. 02, 2011
Segments (Textual) [Abstract]
Segment operating earnings	$ 7,682	$ 7,754	$ 19,158	$ 18,734
Insurance recovery for property damage - casualties		2,687	1,769	2,687
Segments (Additional Textual) [Abstract]
Number reportable segments			2
EMS [Member]
Segments (Textual) [Abstract]
Segment operating earnings	2,375	3,573	5,468	3,947
EMS [Member] | Flood [Member]
Segments (Textual) [Abstract]
Segment operating earnings			5,468
Insurance recovery for property damage - casualties			1,769
EMS [Member] | Fire [Member]
Segments (Textual) [Abstract]
Segment operating earnings		3,573		3,947
Insurance recovery for property damage - casualties		$ 2,687		$ 2,687