Retirement Plans - Changes in Fair Value of Level Three Assets (Details) - Fair Value, Inputs, Level 3 - Private Equity $ in Millions |
12 Months Ended |
|---|---|
|
Dec. 31, 2015
USD ($)
| |
| Defined Benefit Plan Disclosure [Line Items] | |
| Fair value of plan assets at beginning of year | $ 47.3 |
| Unrealized gains-net | 11.9 |
| Purchases, sales and settlements | (14.1) |
| Plan transfer | (45.1) |
| Fair value of plan assets at end of year | $ 0.0 |