Intangible Assets (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Intangible Assets (Textual) [Abstract]
Amortization expense for intangible assets	$ 1,207,000	$ 1,214,000	$ 2,341,884	$ 2,486,737
Database [Member]
Intangible Assets (Textual) [Abstract]
Amount Capitalize Intangible Asset	496,000	491,000	1,024,000	939,000
Amortization expense for intangible assets	383,000	570,000	749,000	1,225,000
Customer relationships [Member]
Intangible Assets (Textual) [Abstract]
Amortization expense for intangible assets	244,000	246,000	488,000	492,000
Web site [Member]
Intangible Assets (Textual) [Abstract]
Amount Capitalize Intangible Asset	549,000	479,000	1,107,000	969,000
Amortization expense for intangible assets	505,000	322,000	954,000	617,000
Acquired below market lease [Member]
Intangible Assets (Textual) [Abstract]
Amortization expense for intangible assets	$ 75,000	$ 75,000	$ 151,000	$ 152,000