Escrow Deposits, Like-Kind Exchange Deposits and Trust Assets (Narrative) (Detail) - USD ($) $ in Billions |
Mar. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Other Assets [Line Items] | ||
| Escrow deposits | $ 7.0 | $ 6.6 |
| Like-kind exchange funds | 2.1 | 2.8 |
| First American Trust | ||
| Other Assets [Line Items] | ||
| Escrow deposits | 2.6 | |
| Trust assets | $ 2.9 | $ 3.0 |