Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The following table presents changes in the carrying amount of goodwill for the years ended December 31, 2018, 2017, and 2016.

Changes in the Carrying Amount of Goodwill

(Dollar amounts in thousands)

	Years Ended December 31,
	2018		2017		2016
Beginning balance	$	697,608	$	340,879	$	319,007
Acquisitions	31,201		356,729		21,872
Ending balance	$	728,809	$	697,608	$	340,879

Schedule of Finite-Lived Intangible Assets

Other Intangible Assets

(Dollar amounts in thousands)

	Years Ended December 31,
	2018							2017							2016
	Gross		Accumulated Amortization		Net			Gross		Accumulated Amortization		Net			Gross		Accumulated Amortization		Net
Beginning balance	$	97,976	$	40,827	$	57,149		$	58,959	$	32,962	$	25,997		$	48,550	$	28,280	$	20,270
Additions	12,230		—		12,230			39,017		—		39,017			10,409		—		10,409
Amortization expense	—		7,444		(7,444		)	—		7,865		(7,865		)	—		4,682		(4,682		)
Ending balance	$	110,206	$	48,271	$	61,935		$	97,976	$	40,827	$	57,149		$	58,959	$	32,962	$	25,997
Weighted-average remaining life (in years)					7.8							8.3							7.6
Estimated remaining useful lives (in years)					0.7 to 9.8							0.2 to 9.3							0.6 to 9.3

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

Scheduled Amortization of Other Intangible Assets

(Dollar amounts in thousands)

	Total
Year Ending December 31,
2019	$	8,296
2020	8,246
2021	8,170
2022	8,090
2023	7,713
2024 and thereafter	21,420
Total	$	61,935