Reserve for Known and Incurred but Not Reported Claims (Summary of Loss Reserves) (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Insurance [Abstract]
Known title claims, amount	$ 77	$ 67
Incurred but not reported claims, amount	1,154	1,143
Total title claims, amount	1,231	1,210
Non-title claims, amount	70	74
Total loss reserves, amount	$ 1,301	$ 1,284	$ 1,203	$ 1,178
Known title claims, percent	5.90%	5.20%
Incurred but not reported claims, percent	88.70%	89.00%
Total title claims, percent	94.60%	94.20%
Non-title claims, percent	5.40%	5.80%
Total loss reserves, percent	100.00%	100.00%