Debt - Schedule of Maturities of Long-term Debt (Details) - Mortgages - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Amortization
2015, amortization	$ 5,943
2016, amortization	12,387
2017, amortization	10,070
2018, amortization	2,880
2019, amortization	2,188
2020 and thereafter, amortization	11,975
Total, amortization	45,443
Maturities
2015, maturities	0
2016, maturities	0
2017, maturities	355,761
2018, maturities	262,210
2019, maturities	535,000
2022, maturities	427,675
Total, maturities	1,580,646
Total long term debt
2015	5,943
2016	12,387
2017	365,831
2018	265,090
2019	537,188
2020 and thereafter	439,650
Total	$ 1,626,089	$ 1,602,062