Commitments and contingencies (Tables)

3 Months Ended

Mar. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Schedule of Financial Instruments with Off-Balance Sheet Credit Risk

	March 31,		December 31,
	2021		2020
Commitments to extend credit, excluding interest rate lock commitments	$	2,613,370	$	2,719,996
Letters of credit	49,578		67,598
Balance at end of period	$	2,662,948	$	2,787,594

Schedule of Allowance of Credit Losses on Unfunded Commitments

The table below presents activity within the allowance for credit losses on unfunded commitments for the three months ended March 31, 2021 and 2020:

	For the Three Months Ended March 31,
	2021		2020
Balance at beginning of period	$	16,378	$	—
Impact of CECL adoption on provision for credit losses on unfunded   commitments	—		2,947
Increase in provision for credit losses from unfunded commitments acquired in business combination	—		70
Provision for credit losses on unfunded commitments	(2,222)		1,601
Balance at end of period	$	14,156	$	4,618

Schedule of Activity in the Repurchase Reserve

The following table summarizes the activity in the repurchase reserve:

	For the Three Months Ended March 31,
	2021		2020
Balance at beginning of period	$	5,928	$	3,529
Provision for loan repurchases or indemnifications	440		372
Losses on loans repurchased or indemnified	(84)		(72)
Balance at end of period	$	6,284	$	3,829