Fair Value Measurements (Financial Assets Measured at Fair Value on Nonrecurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent impaired loans	$ 180,730	$ 184,205
Other real estate owned and foreclosed assets, net	24,900	19,595
Total nonrecurring fair value measurements	205,630	203,800
Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent impaired loans
Other real estate owned and foreclosed assets, net
Total nonrecurring fair value measurements
Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent impaired loans	180,730	184,205
Total nonrecurring fair value measurements	180,730	184,205
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned and foreclosed assets, net	24,900	19,595
Total nonrecurring fair value measurements	$ 24,900	$ 19,595