Revenue Recognition and Valuation Accounts - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2016 |
Jun. 30, 2015 |
Jun. 30, 2016 |
Jun. 30, 2015 |
Dec. 31, 2015 |
|
| Valuation and Qualifying Accounts [Abstract] | |||||
| Allowance for doubtful accounts | $ 5.1 | $ 5.1 | $ 5.2 | ||
| Allowance for contractual discounts | 114.0 | 114.0 | 103.6 | ||
| Allowance for uncompensated care | 31.6 | 31.6 | 41.9 | ||
| Value of uncompensated care to patients | 2.2 | $ 2.3 | 4.7 | $ 4.9 | |
| Estimated cost of charity services | 0.5 | $ 0.5 | 1.2 | $ 1.1 | |
| Inventory valuation reserves | $ 16.6 | $ 16.6 | $ 15.4 | ||