Description of the Company (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2015 USD ($) State	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Segment Reporting Information [Line Items]
Number of states company issues title insurance policies | State	49
Number of states company licensed to issue property and casualty insurance policies | State	50
Number of states company issues property and casualty policies | State	46
Number of states company issues home warranty contracts | State	39
Increase in premiums earned by agent	$ 2,098,265,000	$ 1,867,402,000	$ 2,061,404,000
Increase in personnel costs	1,594,935,000	1,435,628,000	1,488,997,000
Increase in premiums earned by agent	1,656,722,000	1,472,066,000	1,637,561,000
Decrease in operating expenses	820,969,000	807,634,000	841,523,000
Decrease to direct premiums and escrow fees	2,310,047,000	2,052,242,000	2,132,831,000
Information and other	673,138,000	657,197,000	662,736,000
Fair value of investments in debt securities for funding of statutory premium reserves and state deposits	122,400,000	120,700,000
Net other-than-temporary impairment losses	2,200,000	1,700,000
Impairment losses on equity method investments in affiliates	2,000,000	22,500,000	7,800,000
Impairment losses on software	10,900,000	1,200,000	1,100,000
Title plants	528,700,000	514,600,000
Capitalized real estate data	$ 26,200,000	16,000,000
Assessment to determine fair value	50.00%
Goodwill impairment losses	$ 0	$ 0	$ 0
Change in basis points to one or more loss rate	0.50%
Increase (decrease) in IBNR reserve if the expected ultimate losses for each of the last six policy years increase or decrease by 50 basis points	$ 103,200,000
Total premiums assumed and ceded in connection with reinsurance percentage less than premium and escrow fees	1.00%	1.00%	1.00%
Recoveries on reinsured losses related to large commercial title claim	$ 23,800,000
Reinsurance receivable		$ 25,000,000
Escrow deposits	6,600,000,000	6,300,000,000
Like-kind exchange funds	2,800,000,000	2,400,000,000
First American Trust
Segment Reporting Information [Line Items]
Escrow deposits	2,600,000,000	2,200,000,000
Assets held-in-trust	3,000,000,000	3,000,000,000
Accounts and Accrued Income Receivable
Segment Reporting Information [Line Items]
Reinsurance receivable	$ 2,000,000
Incentive Compensation Plan
Segment Reporting Information [Line Items]
Employee stock purchase plan percentage of purchase price on closing price	85.00%
Employee stock purchase plan percentage of discount purchase price on closing price	15.00%
Equity securities
Segment Reporting Information [Line Items]
Net other-than-temporary impairment losses	$ 0	0	$ 0
Unrealized loss position percentage of cost	80.00%
Compensating Errors | Restatement Adjustment
Segment Reporting Information [Line Items]
Decrease in operating expenses		5,000,000
Title Insurance and Services
Segment Reporting Information [Line Items]
Increase in premiums earned by agent		25,800,000	16,500,000
Increase in personnel costs		23,900,000	42,200,000
Increase in premiums earned by agent		1,200,000	800,000
Decrease in operating expenses		(25,100,000)	(43,000,000)
Decrease to direct premiums and escrow fees		(37,200,000)	(35,100,000)
Information and other		37,200,000	35,100,000
Specialty Insurance
Segment Reporting Information [Line Items]
Increase in personnel costs		1,000,000	1,200,000
Decrease in operating expenses		$ (1,000,000)	$ (1,200,000)
Minimum
Segment Reporting Information [Line Items]
Capitalized real estate estimated useful lives, years	3 years
Other intangible assets estimated useful lives, years	1 year
Percentage of claim amounts known in the first few years of the policy life	70.00%
Maximum
Segment Reporting Information [Line Items]
Capitalized real estate estimated useful lives, years	15 years
Other intangible assets estimated useful lives, years	20 years
Percentage of claim amounts known in the first few years of the policy life	80.00%
Buildings | Minimum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	5 years
Buildings | Maximum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	40 years
Furniture and Equipment | Minimum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	1 year
Furniture and Equipment | Maximum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	15 years
Capitalized Software Costs | Minimum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	1 year
Capitalized Software Costs | Maximum
Segment Reporting Information [Line Items]
Property, plant and equipment, estimated useful lives, years	15 years
Leasehold Improvements
Segment Reporting Information [Line Items]
Leasehold improvements, estimated useful lives	Initially recorded at cost and are amortized over the lesser of the remaining term of the respective lease or the estimated useful life, using the straight-line method.