Commitments and Contingencies (Tables)

3 Months Ended

Mar. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

Financial Instruments with Off-Balance-Sheet Risk

Financial instruments with off-balance-sheet risk were as follows:

	March 31, 2020		December 31, 2019
Commitments to extend credit	$	9,204,873	$	9,306,043
Standby letters of credit	268,202		260,587
Deferred standby letter of credit fees	1,773		1,276

Commitments, Off-Balance-Sheet, Allowance for Credit Losses [Table Text Block]

The following table details activity in the allowance for credit losses on off-balance-sheet commitments.

	Three Months Ended   March 31,
	2020		2019
Beginning balance, prior to adoption of ASC 326	$	500	$	500
Impact of adopting ASC 326	39,377		—
Credit loss expense	2,287		—
Ending balance	$	42,164	$	500

Lease Commitments, Components of Lease Expense [Table Text Block]

We lease certain office facilities and office equipment under operating leases. The components of total lease expense were as follows:

	Three Months Ended   March 31,
	2020		2019
Amortization of lease right-of-use assets	$	7,874	$	5,796
Short-term lease expense	561		1,079
Non-lease components (including taxes, insurance, common maintenance, etc.)	2,927		1,733
Total	$	11,362	$	8,608