XML 155 R143.htm IDEA: XBRL DOCUMENT
v3.20.2

Weighted-Average Asset Allocation of Said Plan Assets for Pension Benefits (Detail) - Pension | Mar. 31, 2020
--- | ---
Funds managed by trust |
Weighted-average asset allocation | 100.00%
Government Securities |
Funds managed by trust |
Weighted-average asset allocation | 20.80%
Debenture and bonds |
Funds managed by trust |
Weighted-average asset allocation | 17.10%
Other |
Funds managed by trust |
Weighted-average asset allocation | 62.10%

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

X
- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=hdb_DomesticPensionPlansOfForeignEntityDefinedBenefitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=hdb_GovernmentSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=hdb_DebentureAndBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=hdb_OthersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |