Allowance for Loan and Lease Losses (Summary of Changes in the Allowance for Loan and Lease Losses and Recorded Investments by Portfolio Segment) (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Changes in allowance for loan losses    
Balance at the beginning of the period $ 61,082 $ 58,692
Charge-offs (2,539) (2,542)
Recoveries 305 441
Provision for loan and lease losses excluding unfunded commitments 47,701 1,450
Balance at the end of the period 113,181 58,041
Provisions for credit losses    
Total provision for loan and lease losses 47,701 1,450
Unfunded credit commitments 6,413 (97)
Total provision for credit losses 54,114 1,353
Commercial Real Estate    
Changes in allowance for loan losses    
Balance at the beginning of the period 30,285 28,187
Charge-offs 0 0
Recoveries 0 0
Provision for loan and lease losses excluding unfunded commitments 40,200 162
Balance at the end of the period 82,179 28,349
Provisions for credit losses    
Total provision for loan and lease losses 40,200 162
Commercial    
Changes in allowance for loan losses    
Balance at the beginning of the period 24,826 25,283
Charge-offs (2,527) (2,512)
Recoveries 247 388
Provision for loan and lease losses excluding unfunded commitments 6,900 1,081
Balance at the end of the period 26,774 24,240
Provisions for credit losses    
Total provision for loan and lease losses 6,900 1,081
Consumer    
Changes in allowance for loan losses    
Balance at the beginning of the period 5,971 5,222
Charge-offs (12) (30)
Recoveries 58 53
Provision for loan and lease losses excluding unfunded commitments 601 207
Balance at the end of the period 4,228 5,452
Provisions for credit losses    
Total provision for loan and lease losses 601 $ 207
Adoption of ASU 2016-13 (CECL)    
Changes in allowance for loan losses    
Balance at the beginning of the period 6,632  
Adoption of ASU 2016-13 (CECL) | Commercial Real Estate    
Changes in allowance for loan losses    
Balance at the beginning of the period 11,694  
Adoption of ASU 2016-13 (CECL) | Commercial    
Changes in allowance for loan losses    
Balance at the beginning of the period (2,672)  
Adoption of ASU 2016-13 (CECL) | Consumer    
Changes in allowance for loan losses    
Balance at the beginning of the period $ (2,390)