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Organization and Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2021 subsidiary
Accounting Policies [Abstract]
Number of wholly owned Irish subsidiaries	2

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- Definition

Number Of Irish Subsidiaries

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No definition available.

+ Details

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- References

No definition available.

+ Details

Name:	us-gaap_AccountingPoliciesAbstract
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