Favorable and Unfavorable Acquired Lease Contracts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Intangible assets, net
Weighted average useful life	13 years 6 months
Favorable
Acquired fair value of lease contracts	$ 126,353	$ 126,353
Accumulated (amortization ) accretion	(35,325)	(20,181)
Intangible assets, net	91,028	106,222
Unfavorable
Acquired fair value of lease contracts	(90,113)	(92,093)
Accumulated (amortization ) accretion	28,763	17,963
Total acquired fair value of lease contracts, net	(61,350)	(74,130)
Amortization expense	15,172	16,812	4,024
Expected future amortization of lease contract rights
2015	15,132
2016	14,564
2017	7,190
2018	5,301
2019	5,222
2020 and Thereafter	43,619
Intangible assets, net	91,028	106,222
Expected future (accretion) of lease contract rights
2015	(10,893)
2016	(10,156)
2017	(9,004)
2018	(7,322)
2019	(4,808)
2020 and Thereafter	(19,167)
Total acquired fair value of lease contracts, net	(61,350)	(74,130)
Expected future amortization (accretion) of lease contract rights
2015	(1,244)
2016	(1,596)
2017	(2,498)
2018	(3,263)
2019	(1,175)
2020 and Thereafter	(3,306)
Total	(13,082)
Favorable lease contracts
Intangible assets, net
Weighted average useful life	10 years 9 months 18 days	10 years 1 month 6 days	10 years
Favorable
Acquired fair value of lease contracts	76,955	77,621
Accumulated (amortization ) accretion	(28,687)	(17,587)
Intangible assets, net	48,268	60,034
Unfavorable
Amortization expense	1,016
Expected future amortization of lease contract rights
2015	9,649
2016	8,560
2017	6,506
2018	4,059
2019	3,633
2020 and Thereafter	15,861
Intangible assets, net	48,268	60,034
Unfavorable lease contracts
Intangible assets, net
Weighted average useful life	9 years 9 months 18 days	8 years 10 months 24 days	7 years
Unfavorable
Amortization expense	$ 1,016	$ 4,298	$ 609