Leases - Summary of Reconciles future minimum lease payments (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Mar. 31, 2018
Amounts recognized in the Company's Consolidated Balance Sheet
Lease liability – short term	$ 3,651
Lease liability – long term	20,704
Subtotal	24,355	$ 24,817
Difference between undiscounted and discounted cash flows	8,578
Total future minimum lease payments (undiscounted)	$ 32,933		$ 37,055

Amount of lessee's undiscounted obligation for lease payments for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from 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 (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

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

+ References

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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

Operating lease liability.

+ References

No definition available.

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