Quarterly report pursuant to Section 13 or 15(d)

Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail)

v3.4.0.3
Subsequent Events - Monthly Distributions Declared by Company's Board of Directors (Detail) - Subsequent Event [Member]
Apr. 12, 2016
$ / shares
Senior Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.2625
Series A Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.4843749
Series B Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.4687500
Series C Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.4453125
Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.3750000
Installment 1 - FY2016 [Member]  
Dividends Payable [Line Items]  
Record Date Apr. 22, 2016
Payment Date May 02, 2016
Installment 1 - FY2016 [Member] | Senior Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.0875
Payment Date May 06, 2016
Payable to the Holders of Records During the Month April
Installment 1 - FY2016 [Member] | Series A Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1614583
Installment 1 - FY2016 [Member] | Series B Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1562500
Installment 1 - FY2016 [Member] | Series C Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1484375
Installment 1 - FY2016 [Member] | Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1250000
Installment 2 - FY2016 [Member]  
Dividends Payable [Line Items]  
Record Date May 19, 2016
Payment Date May 31, 2016
Installment 2 - FY2016 [Member] | Senior Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.0875
Payment Date Jun. 07, 2016
Payable to the Holders of Records During the Month May
Installment 2 - FY2016 [Member] | Series A Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1614583
Installment 2 - FY2016 [Member] | Series B Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1562500
Installment 2 - FY2016 [Member] | Series C Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1484375
Installment 2 - FY2016 [Member] | Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1250000
Installment 3 - FY2016 [Member]  
Dividends Payable [Line Items]  
Record Date Jun. 17, 2016
Payment Date Jun. 30, 2016
Installment 3 - FY2016 [Member] | Senior Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.0875
Payment Date Jul. 08, 2016
Payable to the Holders of Records During the Month June
Installment 3 - FY2016 [Member] | Series A Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1614583
Installment 3 - FY2016 [Member] | Series B Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1562500
Installment 3 - FY2016 [Member] | Series C Preferred Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share 0.1484375
Installment 3 - FY2016 [Member] | Common Stock [Member]  
Dividends Payable [Line Items]  
Distribution per Share $ 0.1250000