Credit Concentration - Schedule of ABR (Annualized Base Rent) (Details) - Sales Revenue, Services, Net $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) Rate
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 271,381
Percent of ABR (annualized base rent) | Rate	100.00%
Customer Concentration Risk | CHI - Nebraska
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 16,018
Percent of ABR (annualized base rent) | Rate	5.90%
Customer Concentration Risk | CHI - KentuckyOne Health
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 13,120
Percent of ABR (annualized base rent) | Rate	4.80%
Customer Concentration Risk | Baylor Scott and White Health
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 7,402
Percent of ABR (annualized base rent) | Rate	2.70%
Customer Concentration Risk | US Oncology
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 6,689
Percent of ABR (annualized base rent) | Rate	2.50%
Customer Concentration Risk | CHI - St. Alexius (North Dakota)
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 6,235
Percent of ABR (annualized base rent) | Rate	2.30%
Customer Concentration Risk | Remaining portfolio
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 221,917
Percent of ABR (annualized base rent) | Rate	81.80%
Geographic Concentration Risk | Texas
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 46,900
Percent of ABR (annualized base rent) | Rate	17.30%
Geographic Concentration Risk | Nebraska
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 17,607
Percent of ABR (annualized base rent) | Rate	6.50%
Geographic Concentration Risk | Indiana
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 17,141
Percent of ABR (annualized base rent) | Rate	6.30%
Geographic Concentration Risk | Kentucky
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 16,013
Percent of ABR (annualized base rent) | Rate	5.90%
Geographic Concentration Risk | Arizona
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 14,629
Percent of ABR (annualized base rent) | Rate	5.40%
Geographic Concentration Risk | Other
Concentration Risk [Line Items]
Total ABR (annualized base rent) | $	$ 159,091
Percent of ABR (annualized base rent) | Rate	58.60%