Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Business Combinations - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jan. 07, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill		$ 56,147	$ 58,425
Dynasty Marketplace, Inc.
Business Acquisition [Line Items]
Net tangible assets	$ 305
Identified intangible assets	$ 20,750
Estimated Useful Life (in years)	6 years
Goodwill	$ 42,877
Other noncurrent assets	35
Total assets acquired	63,967
Accrued and other liabilities	48
Deferred tax liability, net	3,711
Total liabilities assumed	3,759
Purchase consideration	60,208
Dynasty Marketplace, Inc. \| Technology
Business Acquisition [Line Items]
Identified intangible assets	$ 5,730
Estimated Useful Life (in years)	4 years
Dynasty Marketplace, Inc. \| Database
Business Acquisition [Line Items]
Identified intangible assets	$ 4,710
Estimated Useful Life (in years)	10 years
Dynasty Marketplace, Inc. \| Customer relationships
Business Acquisition [Line Items]
Identified intangible assets	$ 1,110
Estimated Useful Life (in years)	5 years
Dynasty Marketplace, Inc. \| Backlog
Business Acquisition [Line Items]
Identified intangible assets	$ 470
Estimated Useful Life (in years)	1 year
Dynasty Marketplace, Inc. \| Trademark & trade name
Business Acquisition [Line Items]
Identified intangible assets	$ 1,390
Estimated Useful Life (in years)	10 years
Dynasty Marketplace, Inc. \| Non-compete agreement
Business Acquisition [Line Items]
Identified intangible assets	$ 7,340
Estimated Useful Life (in years)	5 years