XML 79 R68.htm IDEA: XBRL DOCUMENT v3.8.0.1
Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($)
$ in Thousands
Mar. 31, 2018
Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities $ 2,915,648 $ 2,910,869
Derivative assets 4,508 2,148
Derivative liabilities 1,584 3,938
Recurring [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 2,915,648 2,910,869
Derivative assets 12,682 14,157
Total recurring fair value measurements - assets 2,928,330 2,925,026
Derivative liabilities 22,529 14,389
Total recurring fair value measurements - liabilities 22,529 14,389
Recurring [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 2,915,648 2,910,869
Derivative assets 12,682 14,157
Total recurring fair value measurements - assets 2,928,330 2,925,026
Derivative liabilities 22,529 14,389
Total recurring fair value measurements - liabilities 22,529 14,389
Recurring [Member] | U.S. Treasury And Government Agency Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 93,884 97,272
Recurring [Member] | U.S. Treasury And Government Agency Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 93,884 97,272
Recurring [Member] | Municipal Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 237,291 243,786
Recurring [Member] | Municipal Obligations [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 237,291 243,786
Recurring [Member] | Corporate Debt Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 5,500 3,500
Recurring [Member] | Corporate Debt Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 5,500 3,500
Recurring [Member] | Residential Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 1,743,543 1,715,213
Recurring [Member] | Residential Mortgage-Backed Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 1,743,543 1,715,213
Recurring [Member] | Commercial Mortgage-Backed Securities [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 680,272 687,135
Recurring [Member] | Commercial Mortgage-Backed Securities [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 680,272 687,135
Recurring [Member] | Collateralized Mortgage Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities 155,158 163,963
Recurring [Member] | Collateralized Mortgage Obligations [Member] | Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available for sale debt securities $ 155,158 $ 163,963