GOODWILL (Tables)

3 Months Ended

Mar. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in Carrying Amount of Goodwill

Changes in the carrying amount of goodwill for the three months ended March 31, 2021 and March 31, 2020 were as follows:

	Three months ended
	March 31,
(Dollars in thousands)	2021		2020
Balance at beginning of period	$	937,771	$	937,771
Goodwill resulting from business combinations	0		0
Balance at end of period	$	937,771	$	937,771

Finite-Lived Intangible Assets [Line Items]

Schedule of Finite-Lived Intangible Assets [Table Text Block]

(Dollars in thousands)	March 31, 2021				December 31, 2020
	Gross carrying amount		Accumulated amortization		Gross carrying amount		Accumulated amortization
Amortized intangible assets
Core deposit intangibles	$	51,031	$	(28,834)	$	51,031	$	(27,524)
Customer list	39,420		(5,674)		39,420		(4,778)
Other	10,146		(4,105)		10,113		(3,710)
Total	$	100,597	$	(38,613)	$	100,564	$	(36,012)