XML 58 R44.htm IDEA: XBRL DOCUMENT
v3.19.1

Description of Business and Significant Accounting Policies - Investments in Marketable Securities and Inventories and Supplies (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Accounting Policies [Abstract] |  |
Marketable securities, at fair value | $ 76,362 | $ 73,221
Unrealized gains (losses) from marketable securities | $ (800) | $ 1,100
Amortization period of inventories and supplies | 24 months |

X
- Definition Period of Amortization of Inventories and Supplies + References No definition available. + Details
Name: | hcsg_PeriodOfAmortizationOfInventoriesAndSupplies
Namespace Prefix: | hcsg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountingPoliciesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in marketable security, classified as current. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_MarketableSecuritiesCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unrealized gain (loss) on investment in marketable security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_MarketableSecuritiesUnrealizedGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration