Quarterly report pursuant to Section 13 or 15(d)

Available-for-Sale Securities, Weighted Average Life Classifications (Details)

v3.5.0.2
Available-for-Sale Securities, Weighted Average Life Classifications (Details) - USD ($)
$ in Thousands
Sep. 30, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value $ 69,357  
Available-for-sale Securities, Debt Maturities, Year Two Through Three, Fair Value 343,670  
Available-for-sale Securities, Debt Maturities, Year Four Through Five, Fair Value 5,621,618  
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value 7,881,541  
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value 368,439  
Available-for-sale Securities 14,284,625 $ 7,825,320
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value 2,186  
Available-for-sale Securities, Debt Maturities, Year Two Through Three, Fair Value 102,324  
Available-for-sale Securities, Debt Maturities, Year Four Through Five, Fair Value 5,407,166  
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value 6,923,818  
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value 1,322  
Available-for-sale Securities 12,436,816 5,972,890
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value 67,171  
Available-for-sale Securities, Debt Maturities, Year Two Through Three, Fair Value 241,346  
Available-for-sale Securities, Debt Maturities, Year Four Through Five, Fair Value 214,452  
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value 957,723  
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value 367,117  
Available-for-sale Securities $ 1,847,809 $ 1,852,430