Fair Value Measurements Fair Value Nonrecurring Basis (Details) $ in Thousands	Dec. 31, 2018 USD ($) security	Dec. 31, 2017 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number or assets transferred from level 1 to level 2 | security	5
Assets transferred from level 1 to level 2	$ 33,400
Assets:
Loans, net		$ 6,388,297
Fair Value, Inputs, Level 1
Assets:
Loans, net		0
Fair Value, Inputs, Level 2
Assets:
Loans, net		0
Fair Value, Inputs, Level 3
Assets:
Loans, net		6,388,297
Estimate of Fair Value Measurement
Assets:
Loans, net	6,734,216
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 1
Assets:
Loans, net	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2
Assets:
Loans, net	0
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3
Assets:
Loans, net	6,734,216
Estimate of Fair Value Measurement | Fair Value, Measurements, Nonrecurring
Assets:
Loans, net	2,192	1,778
Goodwill		42,054
Total assets	2,192	43,832
Estimate of Fair Value Measurement | Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 1
Assets:
Loans, net	0	0
Goodwill		0
Total assets	0	0
Estimate of Fair Value Measurement | Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 2
Assets:
Loans, net	0	0
Goodwill		0
Total assets	0	0
Estimate of Fair Value Measurement | Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Assets:
Loans, net	2,192	1,778
Goodwill		42,054
Total assets	2,192	43,832
Changes Measurement | Fair Value, Measurements, Nonrecurring
Assets:
Loans, net	(1,648)	(465)
Goodwill		(24,901)
Total assets	$ (1,648)	$ (25,366)