Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Goodwill and Intangibles - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2011	Dec. 31, 2010
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill acquisitions					$ 33,250,000	$ 18,851,000
Goodwill	$ 18,851,000	$ 18,851,000	$ 18,851,000				$ 0
Goodwill impairment charge	$ 33,827,000	0	$ 33,827,000	$ 0
Impairment of indefinite-lived intangible assets		0
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2020		19,274,000
2021		18,723,000
2022		16,935,000
2023		15,866,000
2024		$ 14,378,000