Tax Credit Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Affordable housing tax credit investment, net	$ 139,956		$ 139,956		$ 153,351
Other tax credit investments, net	62,932		62,932		64,354
Total TCIs, net	202,888		202,888		217,705
Unfunded affordable housing tax credit commitments	12,513		12,513		16,684
Other tax credit liabilities	54,823		54,823		55,105
Total unfunded tax credit commitments and liabilities	67,336		67,336		$ 71,789
Affordable housing tax credits and other tax benefits	(7,194)	$ (7,575)	(14,388)	$ (15,150)
Other tax credit investment credits and tax benefits	(941)	(1,135)	(1,882)	(2,271)
Amortization of affordable housing investments, net of tax benefit	5,023	5,494	10,047	10,989
Deferred tax expense	208	239	416	477
Total net reduction in income tax expense	(2,904)	(2,977)	(5,807)	(5,955)
Affordable housing tax credits investment	1,022	823	2,044	1,645
Other tax credit investment amortization	428	669	856	1,338
Total amortization of TCIs	$ 1,450	$ 1,492	$ 2,900	$ 2,983