Employee Benefit Plans (Net Actuarial Loss and Service Benefit) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Compensation and Retirement Disclosure [Abstract]
Net actuarial loss	$ 487
Prior service benefit	$ 1,145

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

No definition available.

Name:	clgx_DefinedBenefitPlanExpectedAmortizationOfPriorServiceCostCreditNextFiscalYear
Namespace Prefix:	clgx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant