Segment Information - Rental Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment revenue information
Rental revenue	$ 976,865	$ 893,457	$ 748,218
Tenant reimbursements	42,015	37,118	24,944
Other revenue	4,405	2,930	7,047
Total revenue	1,023,285	933,505	780,209
Apparel
Segment revenue information
Rental revenue	19,819	17,674	13,851
Automotive service
Segment revenue information
Rental revenue	18,632	16,548	15,606
Automotive tire services
Segment revenue information
Rental revenue	28,627	28,222	27,002
Beverages
Segment revenue information
Rental revenue	25,451	25,147	24,848
Child care
Segment revenue information
Rental revenue	19,949	20,022	20,705
Convenience stores
Segment revenue information
Rental revenue	90,093	89,754	83,973
Dollar stores
Segment revenue information
Rental revenue	88,126	85,049	46,742
Drug stores
Segment revenue information
Rental revenue	103,324	84,625	60,529
Financial services
Segment revenue information
Rental revenue	17,044	16,828	14,904
Grocery stores
Segment revenue information
Rental revenue	29,506	27,270	22,317
Health and fitness
Segment revenue information
Rental revenue	75,881	62,086	46,979
Health care
Segment revenue information
Rental revenue	16,057	16,039	14,358
Home improvement
Segment revenue information
Rental revenue	23,112	15,593	11,456
Restaurants - casual dining
Segment revenue information
Rental revenue	37,645	38,473	38,149
Restaurants - quick service
Segment revenue information
Rental revenue	41,407	33,388	32,340
Theaters
Segment revenue information
Rental revenue	49,456	47,102	46,122
Transportation services
Segment revenue information
Rental revenue	51,745	46,287	40,552
Wholesale clubs
Segment revenue information
Rental revenue	37,391	36,588	29,448
Other non-reportable segments
Segment revenue information
Rental revenue	$ 203,600	$ 186,762	$ 158,337