Quarterly report pursuant to Section 13 or 15(d)

Subsequent Events (Details)

v3.4.0.3
Subsequent Events (Details) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended
Apr. 27, 2016
Apr. 01, 2016
Apr. 30, 2016
Mar. 31, 2016
Mar. 31, 2015
Jan. 27, 2015
Subsequent Event [Line Items]            
Dividends declared per share (in dollars per share)       $ 0.75 $ 0.65  
Common Stock [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Dividends declared per share (in dollars per share) $ 0.750          
Number of shares repurchased     23,400      
Average cost per share repurchased (in dollars per share)     $ 20.26      
Series A Cumulative Redeemable Preferred Stock [Member] | Depositary Shares [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Depositary stock, dividends declared per share (in dollars per share) $ 0.4609375          
Series A Cumulative Redeemable Preferred Stock [Member] | Preferred Stock [Member]            
Subsequent Event [Line Items]            
Coupon rate       7.375%   7.375%
Vantacore Partners LP [Member] | Subsequent Event [Member]            
Subsequent Event [Line Items]            
Final distribution from escrow   $ 1.4