Commitments and Contingencies (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Minimum Period Of Lease Including Renewal Options Operating Leases	5 years
Maximum Period Of Lease Including Renewal Options Operating Leases	35 years
Commitments and Contingencies (Textual) [Abstract]
Additional payment if specified financial criteria are attained based on contractual arrangement	$ 2,200,000	$ 1,500,000
Total rent expense	67,600,000	66,000,000	55,200,000
Total rental income	1,049,000	955,000	920,000
Purchase commitments of products and services through 2016	13,500,000
Business Acquisition, Contingent Consideration, Potential Earnout Payment	2,600,000
Total outstanding holdbacks	886,000.000	2,200,000
Amount paid to sellers for unused portion of holdbacks	$ 2,400,000	$ 2,700,000	$ 1,800,000