| Other comprehensive income, net of tax, gains (losses) on remeasurements of defined benefit plans | en | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| Total other comprehensive income, net of tax, gains (losses) on remeasurements of defined benefit plans | en | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |
| The amount of other comprehensive income, net of tax, related to gains (losses) on remeasurements of defined benefit plans, which comprise actuarial gains and losses; the return on plan assets, excluding amounts included in net interest on the net defined benefit liability (asset); and any change in the effect of the asset ceiling, excluding amounts included in net interest on the net defined benefit liability (asset). [Refer: Other comprehensive income; Defined benefit plans [member]; Plan assets [member]; Net defined benefit liability (asset)] [Contrast: Decrease (increase) in net defined benefit liability (asset) resulting from gain (loss) on remeasurement in other comprehensive income] | en | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Ioncam cuimsitheach eile, glan ó cháin, gnóthachain (caillteanais) ar atomhais ar phleananna sochair shainithe | ga | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |
| An méid ioncaim chuimsithigh eile, glan ó cháin, a bhaineann le gnóthachain (caillteanais) ar atomhais ar phleananna sochair shainithe, lena gcuimsítear gnóthachain agus caillteanais achtúireacha; an toradh ar shócmhainní plean, gan méideanna a áirítear in ús glan ar an nglandliteanas sochair shainithe (sócmhainn) a áireamh; agus aon athrú ar éifeacht na huasteorann sócmhainne, gan méideanna a áirítear in ús glan ar an nglandliteanas sochair shainithe (sócmhainn) a áireamh. [Féach: Ioncam cuimsitheach eile; Pleananna sochair shainithe [member]; Sócmhainní plean [member]; Glandliteanas sochair shainithe (sócmhainn)] [Codarsnacht: Laghdú (méadú) ar ghlandliteanas sochair shainithe (sócmhainn) a eascraíonn as gnóthachan (caillteanas) ar atomhas ioncaim chuimsithigh eile] | ga | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Ioncam cuimsitheach eile, glan ó cháin, gnóthachain (caillteanais) ar atomhais ar phleananna sochair shainithe | ga | http://www.xbrl.org/2003/role/totalLabel | http://www.xbrl.org/2003/role/link |