Goodwill and Other Intangible Assets (Tables)

3 Months Ended

Mar. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of core deposit intangibles and other intangibles

For CDIs and other intangibles, changes in the gross carrying amount, accumulated amortization, and net book value were as follows:

($ in Thousands)	Three Months Ended March 31, 2021		Year Ended December 31, 2020
Core deposit intangibles
Gross carrying amount at the beginning of the year	$	88,109	$	80,730
Additions during the period	—		7,379
Accumulated amortization	(23,408)		(21,205)
Net book value	$	64,701	$	66,904
Amortization during the year	$	2,203	$	8,749
Other intangibles
Gross carrying amount at the beginning of the year	$	2,000	$	38,970
Additions during the period	—		200
Reductions due to sale	(1,317)		(17,435)
Accumulated amortization	(683)		(20,385)
Net book value	$	—	$	1,350
Amortization during the year	$	33	$	1,443

Summary of changes in balance of mortgage servicing rights asset and mortgage servicing rights valuation allowance

A summary of changes in the balance of the MSRs asset and the MSRs valuation allowance is as follows:

($ in Thousands)	Three Months Ended March 31, 2021			Year Ended December 31, 2020
Mortgage servicing rights
Mortgage servicing rights at beginning of period	$	59,967		$	67,607
Additions from acquisition	—			1,357
Additions	3,348			13,667
Amortization	(6,388)			(22,664)
Mortgage servicing rights at end of period	$	56,927		$	59,967
Valuation allowance at beginning of period	$	(18,006)		$	(302)
(Additions) recoveries, net	10,578			(17,704)
Valuation allowance at end of period	$	(7,428)		$	(18,006)
Mortgage servicing rights, net	$	49,500		$	41,961
Fair value of mortgage servicing rights	$	49,541		$	41,990
Portfolio of residential mortgage loans serviced for others (“servicing portfolio”)	$	7,313,308		$	7,743,956
Mortgage servicing rights, net to servicing portfolio	0.68		%	0.54		%
Mortgage servicing rights expense(a)	$	(4,190)		$	40,369

(a) Includes the amortization of mortgage servicing rights and additions / recoveries to the valuation allowance of mortgage servicing rights, and is a component of mortgage banking, net on the consolidated statements of income

Summary of estimated future amortization expense

The following table shows the estimated future amortization expense for amortizing intangible assets:

($ in Thousands)	Core Deposit Intangibles		Mortgage Servicing Rights
Nine Months Ending December 31, 2021	$	6,608	$	8,345
2022	8,811		11,550
2023	8,811		8,909
2024	8,811		6,983
2025	8,811		5,547
2026	8,811		4,466
Beyond 2026	14,038		11,125
Total Estimated Amortization Expense	$	64,701	$	56,927