Present value of lessee's discounted obligation for lease payments from operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- References

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Leases - Schedule of Company's right-of-use lease assets and lease liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Assets:
Total lease assets	$ 93,252	$ 93,358	$ 100,000
Liabilities:
Operating lease liabilities - current	27,764	27,125
Operating lease liabilities - long-term	68,197	66,881
Total lease liabilities	95,961	94,006
Current operating lease liabilities [Member]
Liabilities:
Operating lease liabilities - current	27,764	27,125
Long-term operating lease liabilities [Member]
Liabilities:
Operating lease liabilities - long-term	68,197	66,881
Property Operating lease assets [Member]
Assets:
Total lease assets	62,374	64,206
Automobile Operating lease assets [Member]
Assets:
Total lease assets	29,694	27,197
Automobile Operating lease assets [Member]
Assets:
Total lease assets	1,184	1,955
Equipment operating lease assets [Member]
Assets:
Total lease assets	$ 93,252	$ 93,358