Fair Value Measurements - Financial Assets and Liabilities Carried at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Transfers between Levels
Level 1 to Level 2 transfers, Assets	$ 0		$ 0
Level 2 to Level 1 transfers, Assets	0		0
Level 1 to Level 2 transfers, Liabilities	0		0
Level 2 to Level 1 transfers, Liabilities	0		$ 0
Recurring
Assets:
Equity securities	1,021	$ 1,693
Liabilities:
Contingent consideration	75	75
Recurring \| Significant Unobservable Inputs (Level 3)
Assets:
Equity securities	1,021	1,693
Liabilities:
Contingent consideration	$ 75	$ 75

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Contingent consideration, fair value disclosure.

+ References

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