| Schedule of reclassification from accumulated other comprehensive income into net income | The following table summarizes the amounts reclassified out of accumulated other comprehensive income into net income: 
    |  |  
    |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
    | Accumulated Other Comprehensive |   | Income Statement |   | Three Months Ended September 30, |   | Nine Months Ended September 30, |  
    | Income Components |   | Location |   | 2014 |   | 2013 |   | 2014 |   | 2013 |  
    | Net realized gain (loss) on securities |   |   |   |   |   |   | 
 |   |   | 
 |   |   |  
    | Impairment |   | Other-than-temporary impairment on securities, net of portion of other-than-temporary impairment on securities recognized in other comprehensive income |   | $ | — | 
 |   | $ | — | 
 |   | $ | — | 
 |   | $ | (4,449 | ) |  
    | Gain on settlement of real estate securities |   | Gain (loss) on settlement of investments, net |   | — | 
 |   | 1,381 | 
 |   | 18,032 | 
 |   | 9,590 | 
 |  
    | Loss on settlement of real estate securities |   | Gain (loss) on settlement of investments, net |   | — | 
 |   | — | 
 |   | — | 
 |   | (3,592 | ) |  
    |   |   |   |   | $ | — | 
 |   | $ | 1,381 | 
 |   | $ | 18,032 | 
 |   | $ | 1,549 | 
 |  
    | Net realized gain (loss) on derivatives designated as cash flow hedges |   |   |   |   | 
 |   |   | 
 |   |   |   |   |  
    | Realized loss recognized upon de-designation |   | Other income (loss) |   | $ | (34 | ) |   | $ | — | 
 |   | $ | (34 | ) |   | $ | — | 
 |  
    | Hedge ineffectiveness |   | Other income (loss) |   | $ | (158 | ) |   | $ | — | 
 |   | $ | 101 | 
 |   | $ | — | 
 |  
    | Amortization of deferred gain |   | Interest expense |   | 16 | 
 |   | 1 | 
 |   | 42 | 
 |   | 2 | 
 |  
    | Realized loss reclassified from AOCI into income, related to effective portion |   | Interest expense |   | (1,024 | ) |   | (1,280 | ) |   | (3,481 | ) |   | (4,848 | ) |  
    |   |   |   |   | $ | (1,200 | ) |   | $ | (1,279 | ) |   | $ | (3,372 | ) |   | $ | (4,846 | ) |  
    |   |   |   |   |   |   |   |   |   |   |   |  
    | Total reclassifications |   |   |   | $ | (1,200 | ) |   | $ | 102 | 
 |   | $ | 14,660 | 
 |   | $ | (3,297 | ) |  |