Goodwill and Other Intangible Assets (Tables)

6 Months Ended

Jun. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes in Carrying Amount of Goodwill

The following table shows the changes in the carrying amount of goodwill for the six months ended June 30, 2018 and 2017:

	Six Months Ended June 30,
(dollars in thousands)	2018		2017
Balance at beginning of period	$	828,051	$	655,018
Acquisition adjustments		753		—
Balance at end of period	$	828,804	$	655,018

Schedule of Gross Carrying Amounts and Accumulated Amortization of Other Intangible Assets

The gross carrying amount and accumulated amortization of other intangible assets at June 30, 2018 and December 31, 2017 were as follows:

(dollars in thousands)	Gross Carrying Amount		Accumulated Amortization and Impairment			Net Carrying Amount
June 30, 2018
Core deposit	$	108,268	$	(69,065	)	$	39,203
Customer trust relationships		16,547		(10,333	)		6,214
Total intangible assets	$	124,815	$	(79,398	)	$	45,417
December 31, 2017
Core deposit	$	108,923	$	(62,874	)	$	46,049
Customer trust relationships		16,547		(9,533	)		7,014
Customer loan relationships		4,413		(4,380	)		33
Total intangible assets	$	129,883	$	(76,787	)	$	53,096

Schedule of Estimated Amortization Expense for Future Years

Estimated amortization expense for future years is as follows:

(dollars in thousands)
2018 remaining	$	6,399
2019		11,010
2020		8,672
2021		6,417
2022		4,595
Thereafter		8,324
Total	$	45,417