Income Taxes - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) Provision	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Income Taxes [Line Items]
Reduction in corporate tax rate		21.00%	35.00%	35.00%
Tax code changes description		The TCJA-17 made broad and complex changes to the U.S. tax code, including, but not limited to, (1) reducing the U.S. federal corporate tax rate from 35 percent to 21 percent; (2) requiring companies to pay a one-time transition tax on certain unrepatriated earnings of foreign subsidiaries; (3) generally eliminating U.S. federal income taxes on dividends from foreign subsidiaries; (4) requiring a current inclusion in U.S. federal taxable income of certain earnings of controlled foreign corporations through the implementation of a territorial tax system; (5) creating a new limitation on deductible interest expense; and (6) limiting certain other deductions.
Tax Cuts and Jobs Act of 2017, Accounting Complete [true false]		true	false
Provisional decrease in deferred tax assets			$ 97,000,000
Provisional decrease in deferred tax liabilities			127,000,000
Adjustment to deferred tax benefit			30,000,000
Completion of 2017 tax return, Provisional increase in deferred tax assets	$ 1,000,000	$ 1,000,000
Completion of 2017 tax return, Provisional decrease in deferred tax liabilities	5,000,000	5,000,000
Completion of 2017 tax return, Adjustment to deferred tax benefit	6,000,000	6,000,000
Estimated transition tax obligations			11,300,000
Increase in transition tax		100,000
TCJA 2017, completion of accounting, estimated transition tax obligations		$ 11,400,000
Number of anti-base erosion tax provisions | Provision		2
Income tax expense - BEAT		$ 0
Foreign pre-tax earnings		84,000,000	70,000,000	$ 58,000,000
Unremitted foreign earnings				0
Qualified dividend received deduction		148,000,000
Income tax benefits		$ (236,642,000)	$ (363,697,000)	$ (409,187,000)
Effective tax rates		22.90%	32.00%	35.40%
Deferred federal and state tax benefit		$ 24,000,000	$ 5,000,000
Provisional decrease in deferred tax assets liabilities net due to TCJA-17			30,000,000
Future taxable income, amount		1,120,000,000
Deferred state tax benefit (net of the federal benefit)		(3,592,000)	192,000	$ (820,000)
Deferred foreign tax benefit	7,000,000	7,000,000
Valuation allowances	79,264,000	79,264,000	70,227,000
Increase in estimated liabilities for uncertain tax positions		1,000,000	1,000,000
Impact of unrecognized tax benefits if recognized	1,000,000	$ 1,000,000	1,000,000
Period of expiration of the statute of limitations for certain jurisdictions		Within the next twelve months
Jurisdictions statutes of limitations expiration period		12 months
Allowance in relation to state tax benefit
Income Taxes [Line Items]
Valuation allowances			75,000,000	66,000,000
Net Operating Losses
Income Taxes [Line Items]
Increase in valuation allowance		$ 9,000,000
Foreign Net Operating Losses and Credit Carryforwards
Income Taxes [Line Items]
Increase in valuation allowance		4,000,000	4,000,000
State and Local Jurisdiction
Income Taxes [Line Items]
Deferred state tax benefit (net of the federal benefit)		75,000,000
Interest expense carryforwards	78,000,000	78,000,000
Interest expense, deferred tax benefit	4,000,000	4,000,000
Foreign Tax Authority
Income Taxes [Line Items]
Net operating losses and credit	$ 30,000,000	30,000,000
ASU 2016-09
Income Taxes [Line Items]
Adjustment to deferred tax benefit			30,000,000
Estimated transition tax obligations			11,000,000
Income tax benefits		1,000,000	22,000,000
Excess tax benefit from share based compensation				45,200,000
Net favorable impact of the enactment of the TCJA-17			19,000,000
Unfavorable changes amount due to change in tax rate		21,000,000
Maximum
Income Taxes [Line Items]
Provisional deferred tax - GILTI		$ 1,000,000
Accrued interest and penalties			$ 1,000,000	$ 1,000,000
Foreign and U.S. state and local jurisdictions have statutes of limitations, in years		4 years
Minimum
Income Taxes [Line Items]
Foreign and U.S. state and local jurisdictions have statutes of limitations, in years		3 years