Real Estate and Lending Activities - Concentrations of Credit Risk - Additional Information (Detail) (Concentration of Credit Risks [Member])	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Significant Acquisitions and Disposals [Line Items]
Maximum percentage of entity's total assets invested on single property	4.00%		4.00%
California [Member]
Significant Acquisitions and Disposals [Line Items]
Percentage of total assets accounted			17.10%		18.70%
Texas [Member]
Significant Acquisitions and Disposals [Line Items]
Percentage of total assets accounted			21.10%		22.70%
European [Member] | Minimum [Member]
Significant Acquisitions and Disposals [Line Items]
Percentage of total assets accounted			8.00%
Ernest [Member]
Significant Acquisitions and Disposals [Line Items]
Percentage of entity revenue from affiliates	18.20%	20.40%	18.90%	20.50%
Percentage of total assets accounted	15.10%				15.90%
Prime Health Care Services [Member]
Significant Acquisitions and Disposals [Line Items]
Percentage of entity revenue from affiliates	27.90%	32.50%	28.50%	31.90%
Percentage of total assets accounted			22.30%		24.50%