Income Taxes (Details 2) - USD ($) $ in Thousands		12 Months Ended
Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective income tax rate reconciliation, amount
Computed expected income tax expense (benefit)		$ (18,114)	$ (24,202)	$ (76,449)
Goodwill impairment basis difference		6,000	6,275	36,664
Sold operations basis difference		0	0	686
Net effect of state income taxes		(559)	(954)	178
Foreign subsidiary dividend inclusions		440	843	557
Foreign tax rate differential		187	722	291
Change in valuation allowance		2,265	34,478	(153)
Non-deductible interest		1,280	3,219	715
Stock-based compensation shortfalls		1,373	0	0
Change in valuation allowance due to tax reform		(13,821)	0	0
Change in US tax rate		10,391	0	0
Other, net		664	249	151
Income tax expense (benefit)		$ (9,894)	$ 20,630	$ (37,360)
Effective income tax rate reconciliation, percent
Computed expected income tax expense (benefit)	21.00%	35.00%	35.00%	35.00%
Goodwill impairment basis difference		(11.60%)	(9.10%)	(16.80%)
Sold operations basis difference		0.00%	0.00%	(0.30%)
Net effect of state income taxes		1.10%	1.40%	(0.10%)
Foreign subsidiary dividend inclusions		(0.80%)	(1.20%)	(0.30%)
Foreign tax rate differential		(0.40%)	(1.00%)	(0.10%)
Change in valuation allowance		(4.40%)	(49.90%)	0.10%
Non-deductible interest		(2.50%)	(4.70%)	(0.30%)
Stock-backed compensation shortfalls		(2.70%)	0.00%	0.00%
Change in valuation allowance due to tax reform		26.70%	0.00%	0.00%
Change in US tax rate		(20.10%)	0.00%	0.00%
Other, net		(1.20%)	(0.40%)	(0.10%)
Income tax expense (benefit)		19.10%	(29.90%)	17.10%
Total income tax expense (benefit) allocation
Income tax expense (benefit)		$ (9,894)	$ 20,630	$ (37,360)
Income tax expense, discontinued operations		0	8,994	5,446
Tax effect of gain (loss) from disposal of discontinued operation		0	(4,600)	0
Income tax expense (benefit), stockholders' equity		755	(782)	2,021
Income tax expense, (benefit)		$ (9,139)	$ 24,242	$ (29,893)

Effective Income Tax Rate Reconciliation, Foreign Subsidiary Dividend Inclusions

No definition available.

Name:	hhs_EffectiveIncomeTaxRateReconciliationForeignSubsidiaryDividendInclusions
Namespace Prefix:	hhs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations for dividend.

+ References

No definition available.