XML 162 R148.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Bank loans (Details Textual) | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Bottom of range [member] |  |
Disclosure Of Bank Loans [Line Items] |  |
Borrowings, interest rate | 1.15% | 1.92%
Top of range [member] |  |
Disclosure Of Bank Loans [Line Items] |  |
Borrowings, interest rate | 6.85% | 4.14%

X
- References No definition available. + Details
Name: | cik0001013131_DisclosureOfBankLoansLineItems
Namespace Prefix: | cik0001013131_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The interest rate on borrowings. [Refer: Borrowings] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 7 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_7&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_BorrowingsInterestRate
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |