Other Comprehensive Income (Loss) - Reclassification out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustment for gains included in net income	$ 339	$ 0	$ 465	$ 116
Other non-interest expense	3,260	1,695	5,710	3,246
Income (loss) before income tax expense (benefit)	15,665	(17,703)	34,091	(2,113)
Income tax benefit	(3,634)	2,961	(7,141)	(845)
Net of tax	12,031	(14,742)	26,950	(2,958)
Accumulated Other Comprehensive (Loss) Income Components
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income (loss) before income tax expense (benefit)	(586)	0	(1,384)	789
Income tax benefit	115	0	283	(174)
Net of tax	(471)	0	(1,101)	615
Accumulated Other Comprehensive (Loss) Income Components | Reclassification adjustment for gains included in net income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustment for gains included in net income	339	0	465	116
Accumulated Other Comprehensive (Loss) Income Components | Reclassification adjustment of actuarial net (loss) included in net income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other non-interest expense	$ (925)	$ 0	$ (1,849)	$ 673