Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Additional Cash Flow Information

Additional cash flow information was as follows:

	Nine Months Ended September 30,
	2020		2019
Cash paid for interest	$	41,634	$	100,041
Cash paid for income taxes	44,140		42,352
Significant non-cash transactions:
Unsettled securities transactions	6,698		82,064
Loans foreclosed and transferred to other real estate owned and foreclosed assets	140		1,302
Loans to facilitate the sale of other real estate owned	—		847
Right-of-use lease assets obtained in exchange for lessee operating lease liabilities	18,284		315,542
Treasury stock issued to 401(k) stock purchase plan	6,961		—

Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]

The following table details the impact of the adoption of ASC 326 on the allowance for credit losses as of January 1, 2020.

	January 1, 2020
	Pre-Adoption Allowance		Impact of Adoption		Post-Adoption Allowance		Cumulative Effect on Retained Earnings
Securities held to maturity:
U.S. Treasury	$	—	$	—	$	—	$	—
Residential mortgage-backed securities	—		—		—		—
States and political subdivisions	—		215		215		(170)
Other	—		—		—		—
Total	$	—	$	215	$	215	$	(170)
Loans:
Commercial and industrial	$	51,593	$	21,263	$	72,856	$	(16,798)
Energy	37,382		(10,453)		26,929		8,258
Commercial real estate	31,037		(13,519)		17,518		10,680
Consumer real estate	4,113		2,392		6,505		(1,890)
Consumer and other	8,042		(2,248)		5,794		1,776
Total	$	132,167	$	(2,565)	$	129,602	$	2,026
Off-balance-sheet credit exposures	$	500	$	39,377	$	39,877	$	(31,108)