XML 16 R55.htm IDEA: XBRL DOCUMENT v3.2.0.727
Investment Securities - Summary of Unrealized Losses on Held to Maturity Securities (Details)
$ in Thousands
Jun. 30, 2015
USD ($)
Investment
Dec. 31, 2014
USD ($)
Investment
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost $ 7,735,891 $ 7,421,042
Unrealized Gains 20,686 16,314
Unrealized Losses (25,766) (21,700)
Fair Value 7,730,811 7,415,656
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 3,751,995 3,438,894
Unrealized Losses, Less than 12 months (24,016) (16,520)
Fair Value of Investments, 12 months or longer 167,354 783,558
Unrealized Losses, 12 months or longer (1,750) (5,180)
Fair Value of Investments 3,919,349 4,222,452
Unrealized Losses $ (25,766) $ (21,700)
Number of held-to-maturity investments with unrealized loss | Investment 280 292.000
Number of held-to-maturity investments in continuous loss more than 12 months | Investment 52 26.000
U.S. agency debentures    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost $ 488,185 $ 405,899
Unrealized Gains 7,049 4,589
Unrealized Losses (93) (38)
Fair Value 495,141 410,450
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 15,024 48,335
Unrealized Losses, Less than 12 months (93) (38)
Fair Value of Investments, 12 months or longer 0 0
Unrealized Losses, 12 months or longer 0 0
Fair Value of Investments 15,024 48,335
Unrealized Losses (93) (38)
Agency-issued mortgage-backed securities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 2,590,151 2,799,923
Unrealized Gains 2,280 5,789
Unrealized Losses (4,829) (2,320)
Fair Value 2,587,602 2,803,392
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 1,049,518 999,230
Unrealized Losses, Less than 12 months (4,247) (2,320)
Fair Value of Investments, 12 months or longer 21,869 0
Unrealized Losses, 12 months or longer (582) 0
Fair Value of Investments 1,071,387 999,230
Unrealized Losses (4,829) (2,320)
Residential mortgage-backed securities | Agency-issued collateralized mortgage obligations | Fixed rate    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 3,527,554 3,185,109
Unrealized Gains 6,194 4,521
Unrealized Losses (18,767) (14,885)
Fair Value 3,514,981 3,174,745
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 2,418,601 1,682,348
Unrealized Losses, Less than 12 months (18,649) (9,705)
Fair Value of Investments, 12 months or longer 10,441 783,558
Unrealized Losses, 12 months or longer (118) (5,180)
Fair Value of Investments 2,429,042 2,465,906
Unrealized Losses (18,767) (14,885)
Residential mortgage-backed securities | Agency-issued collateralized mortgage obligations | Variable rate    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 117,109 131,580
Unrealized Gains 285 371
Unrealized Losses (1) 0
Fair Value 117,393 131,951
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 8,150  
Unrealized Losses, Less than 12 months (1)  
Fair Value of Investments, 12 months or longer 0  
Unrealized Losses, 12 months or longer 0  
Fair Value of Investments 8,150  
Unrealized Losses (1)  
Agency-issued commercial mortgage-backed securities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 936,337 814,589
Unrealized Gains 4,870 1,026
Unrealized Losses (1,235) (3,800)
Fair Value 939,972 811,815
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 218,784 629,840
Unrealized Losses, Less than 12 months (671) (3,800)
Fair Value of Investments, 12 months or longer 107,974 0
Unrealized Losses, 12 months or longer (564) 0
Fair Value of Investments 326,758 629,840
Unrealized Losses (1,235) (3,800)
Municipal bonds and notes    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 76,555 83,942
Unrealized Gains 8 18
Unrealized Losses (841) (657)
Fair Value 75,722 83,303
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract]    
Fair Value of Investments, Less than 12 months 41,918 79,141
Unrealized Losses, Less than 12 months (355) (657)
Fair Value of Investments, 12 months or longer 27,070 0
Unrealized Losses, 12 months or longer (486) 0
Fair Value of Investments 68,988 79,141
Unrealized Losses $ (841) $ (657)