Provision for Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Foreign-derived intangible income benefit	$ 28	$ 119	$ 98

Income tax reconciliation foreign derived intangible income benefit.

No definition available.

Name:	cix_IncomeTaxReconciliationForeignDerivedIntangibleIncomeBenefit
Namespace Prefix:	cix_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration