v3.22.4
Intangible Assets
 3 Months Ended
Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]  
Intangible Assets Intangible Assets
The following table provides the gross carrying value, accumulated amortization, net book value and remaining useful life for those intangible assets that are subject to amortization as of December 31, 2022:
Gross Carrying ValueAccumulated AmortizationNet Book ValueWeighted Average Remaining Useful Life (Years)
Accreditations and regulatory approvals$15,600 $— $15,600 Indefinite
Trademarks, trade names and other1,942 (429)1,513 5.69
Curriculum1,900 (118)1,782 4.73
Total$19,442 $(547)$18,895 5.17

The following table provides the gross carrying value, accumulated amortization, net book value and remaining useful life for those intangible assets that are subject to amortization as of December 31, 2021:
Gross Carrying ValueAccumulated AmortizationNet Book ValueWeighted Average Remaining Useful Life (Years)
Accreditations and regulatory approvals - MIAT$12,800 $— $12,800 Indefinite
Trademarks and trade names - MIAT3,000 — 3,000 Indefinite
Curriculum - MIAT400 (13)387 4.83
Non-compete agreement and trade name442 (327)115 3.33
Total$16,642 $(340)$16,302 4.47

Amortization expense for the three months ended December 31, 2022 and 2021 was $120 thousand and $20 thousand, respectively. The increase in the amortization expense during the three months ended December 31, 2022, which is not considered material to the condensed consolidated financial statements, was due to the intangible assets acquired with the Concorde Acquisition.

Of the $19.4 million recorded as intangible assets as of December 31, 2022, $4.8 million relates to the Concorde Acquisition, $14.2 million relates to the MIAT acquisition completed on November 1, 2021, and $0.4 million relates to previously recorded non-compete agreements and trade names. The remaining weighted average useful lives shown are calculated based on the net book value and remaining amortization period of each respective intangible asset. Amortization is computed using the straight-line method based on estimated useful lives of the related assets. Our indefinite-lived intangible assets are reviewed at least annually for impairment as of August 1, or more frequently if there are indicators of impairment. There were no indicators of impairment for our indefinite-lived intangible assets as of December 31, 2022.