Fair Values Measurements - Fair Value Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	$ 114,831	$ 18,070
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	1,220,757
Loans and leases	130,991	57,663
Other real estate owned	17,924	9,397
Repossessed and returned assets	12,603	9,523
Total assets at fair value	1,382,275	76,583
Level 1 | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	0
Loans and leases	0	0
Other real estate owned	0	0
Repossessed and returned assets	0	0
Total assets at fair value	0	0
Level 2 | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	136
Loans and leases	0	0
Other real estate owned	0	0
Repossessed and returned assets	6,841	4,358
Total assets at fair value	6,977	4,358
Level 3 | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	1,220,621
Loans and leases	130,991	57,663
Other real estate owned	17,924	9,397
Repossessed and returned assets	5,762	5,165
Total assets at fair value	$ 1,375,298	$ 72,225