Commitments and Contingencies - Narrative (Details)
$ in Millions
3 Months Ended
Mar. 31, 2015
USD ($)
tenant
claim
Commitments and Contingencies Disclosure [Abstract]  
Outstanding claims | claim 0
Total commitments $ 194.7
Total commitments relating to future acquisitions 185.3
Contingently liable amount of debt owed by tenant $ 5.7
Number of tenants indemnified by | tenant 1