Tax Credit Investments (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Affordable housing tax credit investment, net	$ 169,096		$ 170,401
Other tax credit investments, net	73,859		72,584
Total community development investments, net	242,955		242,985
Unfunded affordable housing tax credit commitments	21,635		23,196
Other tax credit investment liabilities	61,506		59,823
Total unfunded tax credit investment commitments and liabilities	83,141		$ 83,019
Affordable housing tax credits and other tax benefits	(7,575)	$ (7,544)
Other tax credit investment credits and tax benefits	(1,136)	(1,596)
Amortization of affordable housing investments, net of tax benefit	5,495	5,598
Deferred tax expense	238	335
Total reduction in income tax expense	2,978	3,207
Affordable housing tax credits investment	822	839
Other tax credit investment amortization	669	798
Total amortization of tax credit investments	$ 1,491	$ 1,637