Label	Element	Value
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	us-gaap_StockIssuedDuringPeriodValueStockOptionsExercisedNetOfTaxBenefitExpense	$ 1,800,000
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition	us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	(64,100,000)
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	1,427,600,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	1,693,900,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	1,989,800,000
Stock Repurchased and Retired During Period, Value	us-gaap_StockRepurchasedAndRetiredDuringPeriodValue	1,000,000.0
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	us-gaap_TaxCutsAndJobsActOf2017ReclassificationFromAociToRetainedEarningsTaxEffect	0
Stock Issued During Period, Value, New Issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	173,300,000
Common Stock Including Additional Paid in Capital [Member]
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	us-gaap_StockIssuedDuringPeriodValueStockOptionsExercisedNetOfTaxBenefitExpense	1,800,000
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	0
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition	us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	0
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	866,700,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	687,000,000.0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	1,049,300,000
Stock Repurchased and Retired During Period, Value	us-gaap_StockRepurchasedAndRetiredDuringPeriodValue	1,000,000.0
Stock Issued During Period, Value, New Issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	173,300,000
Net Income (Loss) Attributable to Parent	us-gaap_NetIncomeLoss	0
Retained Earnings [Member]
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	us-gaap_StockIssuedDuringPeriodValueStockOptionsExercisedNetOfTaxBenefitExpense	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	0
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition	us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	(64,100,000)
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0
Share-based Payment Arrangement, Expense	us-gaap_AllocatedShareBasedCompensationExpense	0
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	851,800,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	752,600,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	929,500,000
Stock Repurchased and Retired During Period, Value	us-gaap_StockRepurchasedAndRetiredDuringPeriodValue	0
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	us-gaap_TaxCutsAndJobsActOf2017ReclassificationFromAociToRetainedEarningsTaxEffect	3,100,000
Stock Issued During Period, Value, New Issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	0
Net Income (Loss) Attributable to Parent	us-gaap_NetIncomeLoss	160,200,000
AOCI Attributable to Parent [Member]
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	us-gaap_StockIssuedDuringPeriodValueStockOptionsExercisedNetOfTaxBenefitExpense	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	(9,500,000)
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition	us-gaap_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationStockOptionsRequisiteServicePeriodRecognition	0
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	0
Share-based Payment Arrangement, Expense	us-gaap_AllocatedShareBasedCompensationExpense	0
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	24,600,000
Dividends, Common Stock, Cash	us-gaap_DividendsCommonStockCash	12,000,000.0
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	11,000,000.0
Stock Repurchased and Retired During Period, Value	us-gaap_StockRepurchasedAndRetiredDuringPeriodValue	0
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	us-gaap_TaxCutsAndJobsActOf2017ReclassificationFromAociToRetainedEarningsTaxEffect	(3,100,000)
Stock Issued During Period, Value, New Issues	us-gaap_StockIssuedDuringPeriodValueNewIssues	0
Net Income (Loss) Attributable to Parent	us-gaap_NetIncomeLoss	$ 0