XML 172 R156.htm IDEA: XBRL DOCUMENT v3.8.0.1
Employee Benefits - Summary of Sensitivity Analysis on Defined Benefit Obligation of Defined Benefit Pension Plans (Detail)
₱ in Millions
Dec. 31, 2017
PHP (₱)
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]  
Percentage of decrease in defined benefit obligation (20.00%)
Actuarial assumption of discount rates [Member]  
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]  
Increase (decrease) in defined benefit obligation due to 1% increase ₱ (2,262)
Increase (decrease) in defined benefit obligation due to 1% decrease ₱ 2,638
Percentage of increase in defined benefit obligation 1.00%
Percentage of decrease in defined benefit obligation (1.00%)
Actuarial assumption of discount rates [Member] | Defined Contribution Plans [member]  
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]  
Increase (decrease) in defined benefit obligation due to 1% increase ₱ 11
Increase (decrease) in defined benefit obligation due to 1% decrease ₱ (6)
Percentage of increase in defined benefit obligation 1.00%
Percentage of decrease in defined benefit obligation (1.00%)
Actuarial assumption of expected rates of salary increases [Member]  
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]  
Increase (decrease) in defined benefit obligation due to 1% increase ₱ 2,606
Increase (decrease) in defined benefit obligation due to 1% decrease ₱ (2,288)
Percentage of increase in defined benefit obligation 1.00%
Percentage of decrease in defined benefit obligation (1.00%)
Actuarial assumption of expected rates of salary increases [Member] | Defined Contribution Plans [member]  
Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items]  
Increase (decrease) in defined benefit obligation due to 1% increase ₱ 11
Increase (decrease) in defined benefit obligation due to 1% decrease ₱ (6)
Percentage of increase in defined benefit obligation 1.00%
Percentage of decrease in defined benefit obligation (1.00%)