Subsequent Events (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Aug. 04, 2015 USD ($) Property $ / shares shares	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Subsequent Event [Line Items]
Payments to acquire remaining interest			$ 197,926	$ 51,962
Impairment of real estate			$ 1,252	$ 16,400
Baltimore, Maryland [Member] | Scenario, Forecast [Member]
Subsequent Event [Line Items]
Impairment of real estate		$ 28,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of real estate properties sold | Property	2
Proceeds from sale of property held-for-sale	$ 14,650
Authorized amount for repurchase (in shares) | shares	10,000,000
Payments for repurchase of common stock	$ 1,289
Subsequent Event [Member] | Common Stock [Member]
Subsequent Event [Line Items]
Stock repurchased during period (in shares) | shares	150,000
Subsequent Event [Member] | Series C [Member]
Subsequent Event [Line Items]
Dividends declared on preferred stock (usd per share) | $ / shares	$ 0.8125
Subsequent Event [Member] | Westmont, Illinios [Member]
Subsequent Event [Line Items]
Cash acquired through foreclosure	$ 2,521
Litigation settlement, amount	1,400
Subsequent Event [Member] | Philadelphia, Pennsylvania [Member] | Office Building [Member]
Subsequent Event [Line Items]
Payments to acquire remaining interest	4,022
Subsequent Event [Member] | Baltimore, Maryland [Member]
Subsequent Event [Line Items]
Expected proceeds from sale of real estate	121,000
Expected proceeds from sale of real estate, mortgage assumption	$ 55,000