Quarterly report pursuant to Section 13 or 15(d)

Schedule of Company's Board had declared cash dividends on common stock (Details)

v3.10.0.1
Schedule of Company's Board had declared cash dividends on common stock (Details) - USD ($)
$ / shares in Units, $ in Thousands
6 Months Ended
Jun. 30, 2018
Dec. 31, 2017
Record Date Jul. 15, 2018  
Dividend Amount $ 5,940 $ 5,638
Common Stock [Member] | Dividend Declared On 15 December    
Record Date Dec. 26, 2017  
Applicable Quarter Q4 2017  
Payment Date Jan. 10, 2018  
Dividend Amount $ 4,552  
Dividends per Share $ 0.20  
Common Stock [Member] | Dividend Declared On 07 March    
Record Date Mar. 22, 2018  
Applicable Quarter Q1 2018  
Payment Date Apr. 10, 2018  
Dividend Amount $ 4,691  
Dividends per Share $ 0.20  
Common Stock [Member] | Dividend Declared On 15 June    
Record Date Jun. 26, 2018  
Applicable Quarter Q2 2018  
Payment Date Jul. 11, 2018  
Dividend Amount $ 4,786  
Dividends per Share $ 200  
Preferred Stock [Member] | Dividend Declared On 15 December    
Record Date Jan. 15, 2018  
Applicable Quarter Q4 2017  
Payment Date Jan. 31, 2018  
Dividend Amount $ 1,455  
Amount Accrued $ 0  
Dividends per Share $ 0.46875  
Preferred Stock [Member] | Dividend Declared On 07 March    
Record Date Apr. 15, 2018  
Applicable Quarter Q1 2018  
Payment Date Apr. 30, 2018  
Dividend Amount $ 1,456  
Amount Accrued $ 0  
Dividends per Share $ 0.46875  
Preferred Stock [Member] | Dividend Declared On 15 June    
Applicable Quarter Q2 2018  
Payment Date Jul. 31, 2018  
Dividend Amount $ 1,455  
Amount Accrued $ 970  
Dividends per Share $ 0.46875