SIGNIFICANT ACCOUNTING POLICIES - Accounts Receivable, Net (Details)	12 Months Ended
Dec. 31, 2017
SIGNIFICANT ACCOUNTING POLICIES
Minimum period of receivable balances for which an evaluation of its collectability is performed	1 year
Adjudication period of receivable balances for which an evaluation of its collectability is performed	12 months

Represents the adjudication period of receivable balances for which company-wide evaluation of its collectability is performed at least semi-annually.

No definition available.

Name:	hgr_RevenueRecognitionCustomerAgingAnalysisAdjudicationPeriod
Namespace Prefix:	hgr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration