Income Taxes (Reconciliation Of Effective Income Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of income tax computed at the U.S. federal statutory tax rate to the entity's effective income tax rate for continuing operations
Tax at U.S. federal statutory rate (as a percent)	21.00%	21.00%	21.00%
State and local income taxes, net of U.S. federal benefit (as a percent)	6.60%	15.10%	2.60%
Foreign rate differences (as a percent)	2.20%	2.10%	0.80%
Tax credits (as a percent)	(1.10%)	(5.20%)	(3.50%)
Realized (gain) loss on investment in frontdoor, inc. (as a percent)			(13.30%)
Limitation on executive compensation (as a percent)	0.80%	2.70%	1.20%
Excess tax benefits from stock-based compensation (as a percent)	(0.30%)	0.30%	(1.80%)
Mobile Bay Formosan termite settlement (as a percent)		20.30%
Tax reserves (as a percent)	(0.10%)	(2.70%)	0.30%
Other items (as a percent)	1.20%	3.70%	0.20%
Valuation allowance	1.10%	0.80%	(0.20%)
Effective rate (as a percent)	31.40%	58.10%	7.30%