Income Taxes - Income Tax Provision (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income Taxes
Statutory income tax rate (as a percent)	21.00%	34.00%
U.S. Federal (benefit) provision
At statutory rate	$ (27,235)	$ (2,649)
State taxes	(358)	34
Federal Valuation allowance	23,792	(8,431)
Foreign tax adjustments	(2,332)	81
Disallowed interest expense		190
Federal tax rate change		7,338
Permanent Adjustments	236
Effect of uncertain tax positions	(30)	10
Book income from pre-transaction period		(1,932)
Other		28
Total	$ (5,927)	$ (5,331)
Effective tax rate from continuing operations (as a percent)	4.60%
Benefit due to the impact of the Tax Act (as a percent)		68.40%

No definition available.

Name:	ctrc_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestAmount
Namespace Prefix:	ctrc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations, attributable to increase (decrease) in income tax rate and transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act of 2017.

+ References

No definition available.