XML 68 R49.htm IDEA: XBRL DOCUMENT v3.8.0.1
Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details) - USD ($)
$ in Thousands
Dec. 31, 2017
Dec. 31, 2016
Statement [Line Items]    
Available-for-sale securities, amortized cost basis $ 2,575,719 $ 2,594,255
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 13,062 24,807
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (40,825) (59,835)
Available-for-sale Securities 2,547,956 2,559,227
U.S. Government sponsored agency securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 5,962 132
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 2 2
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (26) 0
Available-for-sale Securities 5,938 134
State and municipal securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 405,860 405,274
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 5,638 2,043
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (2,549) (15,676)
Available-for-sale Securities 408,949 391,641
Corporate debt securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 96,353 112,016
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 2,832 1,978
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (1,876) (4,585)
Available-for-sale Securities 97,309 109,409
Collateralized mortgage obligations    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 611,927 604,095
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 491 1,943
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (9,795) (12,178)
Available-for-sale Securities 602,623 593,860
Residential mortgage-backed securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 1,132,080 1,328,192
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 3,957 6,546
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (15,241) (16,900)
Available-for-sale Securities 1,120,796 1,317,838
Residential mortgage-backed securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 215,351 25,100
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 0 0
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (2,596) (537)
Available-for-sale Securities 212,755 24,563
Auction rate securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 107,410 107,215
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 0 0
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (8,742) (9,959)
Available-for-sale Securities 98,668 97,256
Debt securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 2,574,943 2,582,024
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 12,920 12,512
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments (40,825) (59,835)
Available-for-sale Securities 2,547,038 2,534,701
Equity securities    
Statement [Line Items]    
Available-for-sale securities, amortized cost basis 776 12,231
Available-for-sale Securities, Gross Unrealized Gain, Accumulated Investments 142 12,295
Available-for-sale Securities, Gross Unrealized Loss, Accumulated Investments 0 0
Available-for-sale Securities $ 918 $ 24,526