Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Fair Value Measurements (Textual) [Abstract]
Impaired loans not covered under loss-share agreements	$ 16,315		$ 22,621
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Specific reserve included in allowance for loan losses	50,059		49,026
Changes in fair value, gain (loss)	3,534	$ 4,177
Impaired Loans, Not Covered
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Specific reserve included in allowance for loan losses	$ 1,569		$ 935