Balance Sheet Offsetting (Details) - Interest Rate Contract - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	[1]	$ 17,504	$ 65,596
Gross amounts offset in the balance sheet	[1]	0	0
Net amounts presented in the balance sheet	[1]	17,504	65,596
Derivative liability available for offset	[1]	(6,693)	(22,873)
Collateral	[1]	(8,339)	(41,879)
Net amount	[1]	2,472	843
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	[1]	17,045	22,951
Gross amounts offset in the balance sheet	[1]	0	0
Net amounts presented in the balance sheet	[1]	17,045	22,951
Derivative asset available for offset	[1]	(6,693)	(22,873)
Collateral	[1]	(10,179)	(63)
Net amount	[1]	$ 174	$ 16

[1] (a) Includes interest, commodity, and foreign exchange agreements