XML 105 R79.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Retirement and Pension Plans (Schedule of Net Periodic benefit Cost for Defined Benefit Pension and Severance Plans) (Details) (JPY ¥)
In Millions, unless otherwise specified
12 Months Ended
Mar. 31, 2011
Mar. 31, 2010
Mar. 31, 2009
Retirement and Pension Plans      
Service cost ¥ 6,117 ¥ 5,933 ¥ 5,944
Interest cost 3,315 3,646 3,730
Expected return on plan assets (2,585) (2,200) (2,428)
Amortization of prior service benefit (808) (808) (808)
Amortization of actuarial loss 472 9,611 128
Total ¥ 6,511 ¥ 16,182 ¥ 6,566
Expected return on plan assets 2.50% [1] 2.50% [1] 2.50% [1]
Discount rate 2.40% [1] 2.50% [1] 2.50% [1]
Percentage of net actuarial losses in excess of projected benefit obligation   20.00%  
[1] The rate of compensation increase is not used in the calculations of benefit obligations under the point-based benefits system.