Schedule II (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	$ 7,400	$ 7,761	$ 7,014
Additions	5,479	4,983	3,320
Deductions	(5,981)	(5,344)	(2,573)
Balance at End of the Year	6,898	7,400	7,761
Allowance for Trade Receivable, Straight Line Rent [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	910	823	798
Additions	1,233	1,097	815
Deductions	(1,562)	(1,010)	(790)
Balance at End of the Year	581	910	823
Allowance for Trade Receivables [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of the Year	6,490	6,938	6,216
Additions	4,246	3,886	2,505
Deductions	(4,419)	(4,334)	(1,783)
Balance at End of the Year	$ 6,317	$ 6,490	$ 6,938