$SEIC
SEI INVESTMENTS CO Stock $seic

$seic Overview Financials Valuation SEC Filings Company Website

2018 Q4 Form 10-Q Financial Statement

#000035089418000053 Filed on October 25, 2018

Income Statement

Concept	2018 Q4	2018 Q3	2017 Q3
Revenue	$405.1M	$408.7M	$386.0M
YoY Change	-0.77%	5.87%	8.85%
Cost Of Revenue	$71.50M	$69.70M	$75.60M
YoY Change	-8.92%	-7.8%	5.0%
Gross Profit	$333.5M	$127.4M	$114.7M
YoY Change	1.15%	11.01%	1.39%
Gross Profit Margin	82.33%	31.16%	29.72%
Selling, General & Admin	$210.8M	$206.9M	$190.5M
YoY Change	2.43%	8.61%	13.8%
% of Gross Profit	63.21%	162.45%	166.04%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$19.80M	$7.255M	$6.948M
YoY Change	16.47%	4.42%	5.66%
% of Gross Profit	5.94%	5.7%	6.06%
Operating Expenses	$230.6M	$226.6M	$211.2M
YoY Change	3.5%	7.29%	13.92%
Operating Profit	$102.9M	$112.4M	$99.24M
YoY Change	-3.74%	13.28%	2.08%
Interest Expense	$40.60M	$122.0K	$345.0K
YoY Change	-10.77%	-64.64%	200.0%
% of Operating Profit	39.46%	0.11%	0.35%
Other Income/Expense, Net
YoY Change
Pretax Income	$143.6M	$157.6M	$140.8M
YoY Change	-5.81%	11.95%	7.55%
Income Tax	$28.80M	$29.28M	$39.03M
% Of Pretax Income	20.06%	18.58%	27.73%
Net Earnings	$116.0M	$128.3M	$101.7M
YoY Change	-5.0%	26.13%	17.34%
Net Earnings / Revenue	28.65%	31.4%	26.36%
Basic Earnings Per Share	$0.75	$0.82	$0.64
Diluted Earnings Per Share	$0.73	$0.80	$0.63
COMMON SHARES
Basic Shares Outstanding	155.5M shares	156.8M shares	158.1M shares
Diluted Shares Outstanding		160.5M shares	161.1M shares

Balance Sheet

Concept	2018 Q4	2018 Q3	2017 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$785.4M	$770.9M	$706.4M
YoY Change	2.56%	9.13%	9.6%
Cash & Equivalents	$754.5M	$742.0M	$685.0M
Short-Term Investments	$30.90M	$28.90M	$21.50M
Other Short-Term Assets	$36.68M	$37.11M	$30.54M
YoY Change	17.71%	21.53%	0.85%
Inventory
Prepaid Expenses
Receivables	$315.3M	$371.5M	$311.4M
Other Receivables	$13.70M	$10.50M	$13.10M
Total Short-Term Assets	$1.191B	$1.194B	$1.065B
YoY Change	4.47%	12.07%	9.03%
LONG-TERM ASSETS
Property, Plant & Equipment	$145.9M	$145.9M	$148.1M
YoY Change	-0.39%	-1.51%	-0.77%
Goodwill	$64.49M	$64.49M
YoY Change	21.7%
Intangibles	$31.67M	$32.59M
YoY Change	10.82%
Long-Term Investments	$169.1M	$134.7M	$130.2M
YoY Change	10.16%	3.46%	-5.24%
Other Assets	$34.16M	$33.64M	$17.05M
YoY Change	80.87%	97.37%	6.11%
Total Long-Term Assets	$780.9M	$745.8M	$686.4M
YoY Change	9.43%	8.65%	15.02%
TOTAL ASSETS
Total Short-Term Assets	$1.191B	$1.194B	$1.065B
Total Long-Term Assets	$780.9M	$745.8M	$686.4M
Total Assets	$1.972B	$1.939B	$1.751B
YoY Change	6.38%	10.73%	11.3%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$10.92M	$9.161M	$4.429M
YoY Change	107.29%	106.84%	-36.8%
Accrued Expenses	$279.6M	$207.7M	$185.4M
YoY Change	5.5%	12.03%	8.56%
Deferred Revenue	$5.154M	$5.054M
YoY Change	9.13%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$295.7M	$221.9M	$192.9M
YoY Change	7.51%	15.01%	6.75%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$40.00M
YoY Change	-100.0%	-100.0%
Other Long-Term Liabilities	$24.22M	$26.00M	$16.20M
YoY Change	95.6%	60.49%	14.89%
Total Long-Term Liabilities	$24.22M	$26.00M	$56.20M
YoY Change	95.6%	-53.74%	298.58%
TOTAL LIABILITIES
Total Short-Term Liabilities	$295.7M	$221.9M	$192.9M
Total Long-Term Liabilities	$24.22M	$26.00M	$56.20M
Total Liabilities	$378.5M	$308.8M	$318.9M
YoY Change	0.53%	-3.15%	22.47%
SHAREHOLDERS EQUITY
Retained Earnings	$518.0M	$556.6M	$448.4M
YoY Change	10.8%	24.14%	11.87%
Common Stock	$1.108B	$1.103B	$1.004B
YoY Change	7.67%	9.79%	6.52%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.593B	$1.631B	$1.433B
YoY Change
Total Liabilities & Shareholders Equity	$1.972B	$1.939B	$1.751B
YoY Change	6.38%	10.73%	11.3%

Cashflow Statement

Concept	2018 Q4	2018 Q3	2017 Q3
OPERATING ACTIVITIES
Net Income	$116.0M	$128.3M	$101.7M
YoY Change	-5.0%	26.13%	17.34%
Depreciation, Depletion And Amortization	$19.80M	$7.255M	$6.948M
YoY Change	16.47%	4.42%	5.66%
Cash From Operating Activities	$170.5M	$155.0M	$131.5M
YoY Change	18.82%	17.87%	4.45%
INVESTING ACTIVITIES
Capital Expenditures	-$18.30M	-$17.70M	-$25.40M
YoY Change	3.39%	-30.31%	-18.85%
Acquisitions
YoY Change
Other Investing Activities	-$27.70M	$4.200M	-$75.90M
YoY Change	326.15%	-105.53%	1846.15%
Cash From Investing Activities	-$46.00M	-$13.50M	-$101.2M
YoY Change	90.08%	-86.66%	188.32%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-107.5M	-92.50M	-11.90M
YoY Change	79.47%	677.31%	-80.27%
NET CHANGE
Cash From Operating Activities	170.5M	155.0M	131.5M
Cash From Investing Activities	-46.00M	-13.50M	-101.2M
Cash From Financing Activities	-107.5M	-92.50M	-11.90M
Net Change In Cash	17.00M	49.00M	18.40M
YoY Change	-71.38%	166.3%	-39.67%
FREE CASH FLOW
Cash From Operating Activities	$170.5M	$155.0M	$131.5M
Capital Expenditures	-$18.30M	-$17.70M	-$25.40M
Free Cash Flow	$188.8M	$172.7M	$156.9M
YoY Change	17.12%	10.07%	-0.19%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2018
	dei	Document Period End Date DocumentPeriodEndDate	2018-09-30
	dei	Entity Central Index Key EntityCentralIndexKey	0000350894
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Trading Symbol TradingSymbol	SEIC
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	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	122342000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	128319000	USD
CY2017Q3	us-gaap	Profit Loss ProfitLoss	101739000	USD
	us-gaap	Profit Loss ProfitLoss	389834000	USD
	us-gaap	Profit Loss ProfitLoss	282245000	USD
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.48
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.78
CY2018Q3	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	156283000	shares
CY2017Q3	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	157902000	shares
	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	157086000	shares
	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	158439000	shares
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.41
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.74
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	160511000	shares
CY2017Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161148000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	162053000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161866000	shares
CY2018Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0
CY2017Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2018Q3	us-gaap	Profit Loss ProfitLoss	128319000	USD
CY2017Q3	us-gaap	Profit Loss ProfitLoss	101739000	USD
	us-gaap	Profit Loss ProfitLoss	389834000	USD
	us-gaap	Profit Loss ProfitLoss	282245000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-435000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	7318000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-7261000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	17028000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-337000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	294000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1662000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	435000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-130000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-207000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-105000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	399000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	32000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-1694000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-194000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	629000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-642000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7717000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-8955000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	17657000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	127677000	USD
CY2017Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	109456000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	380879000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	299902000	USD
	us-gaap	Profit Loss ProfitLoss	389834000	USD
	us-gaap	Profit Loss ProfitLoss	282245000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	28064000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	34142000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	417898000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	316387000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	21652000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	20318000	USD
	us-gaap	Payments For Software PaymentsForSoftware	33371000	USD
	us-gaap	Payments For Software PaymentsForSoftware	48573000	USD
	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	122259000	USD
	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	50235000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	116568000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	52644000	USD
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	5794000	USD
	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	80131000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	10900000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	1450000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-77408000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-148063000	USD
	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	0	USD
	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	40000000	USD
	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	30000000	USD
	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	0	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	290563000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	186494000	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	78667000	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	41626000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	94318000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	88862000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-336214000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-193730000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-6552000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	14679000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2276000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-10727000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	747752000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	699201000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	745476000	USD
CY2017Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	688474000	USD
CY2018Q3	seic	Expense Related To Soft Dollar Arrangement ExpenseRelatedToSoftDollarArrangement	3265000	USD
CY2017Q3	seic	Expense Related To Soft Dollar Arrangement ExpenseRelatedToSoftDollarArrangement	3297000	USD
	seic	Expense Related To Soft Dollar Arrangement ExpenseRelatedToSoftDollarArrangement	10497000	USD
	seic	Expense Related To Soft Dollar Arrangement ExpenseRelatedToSoftDollarArrangement	10799000	USD
	us-gaap	Capitalized Computer Software Additions CapitalizedComputerSoftwareAdditions	33371000	USD
	us-gaap	Capitalized Computer Software Additions CapitalizedComputerSoftwareAdditions	48573000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	128319000	USD
CY2017Q3	us-gaap	Profit Loss ProfitLoss	101739000	USD
	us-gaap	Profit Loss ProfitLoss	389834000	USD
	us-gaap	Profit Loss ProfitLoss	282245000	USD
CY2018Q3	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	156283000	shares
CY2017Q3	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	157902000	shares
	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	157086000	shares
	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	158439000	shares
CY2018Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	4228000	shares
CY2017Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	3246000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	4967000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	3427000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	160511000	shares
CY2017Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161148000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	162053000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	161866000	shares
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.48
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.78
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.80
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.41
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.74
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	6183000	shares
CY2017Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	11324000	shares
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Net Income Per Outstanding Unit Amount AntidilutiveSecuritiesExcludedFromComputationOfNetIncomePerOutstandingUnitAmount	53.38
CY2017Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Net Income Per Outstanding Unit Amount AntidilutiveSecuritiesExcludedFromComputationOfNetIncomePerOutstandingUnitAmount	37.81
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	6153000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	11286000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Net Income Per Outstanding Unit Amount AntidilutiveSecuritiesExcludedFromComputationOfNetIncomePerOutstandingUnitAmount	53.15
	us-gaap	Antidilutive Securities Excluded From Computation Of Net Income Per Outstanding Unit Amount AntidilutiveSecuritiesExcludedFromComputationOfNetIncomePerOutstandingUnitAmount	37.73
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	ReclassificationsCertain prior year amounts have been reclassified to conform to current year presentation.
	us-gaap	Profit Loss ProfitLoss	389834000	USD
	us-gaap	Profit Loss ProfitLoss	282245000	USD
	us-gaap	Depreciation Nonproduction DepreciationNonproduction	21515000	USD
	us-gaap	Depreciation Nonproduction DepreciationNonproduction	20347000	USD
	us-gaap	Amortization Of Deferred Charges AmortizationOfDeferredCharges	36420000	USD
	us-gaap	Amortization Of Deferred Charges AmortizationOfDeferredCharges	38332000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	123406000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	109213000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	138216000	USD
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	117447000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	16396000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	19527000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	-29000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	176000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-8378000	USD
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-1143000	USD
	us-gaap	Gain Loss On Investments Excluding Other Than Temporary Impairments GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments	-460000	USD
	us-gaap	Gain Loss On Investments Excluding Other Than Temporary Impairments GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments	1036000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-9859000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	0	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	1930000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	106000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	4214000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-79000	USD
	seic	Capitalized Contract Costs Net Of Amortization CapitalizedContractCostsNetOfAmortization	3463000	USD
	seic	Capitalized Contract Costs Net Of Amortization CapitalizedContractCostsNetOfAmortization	0	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	99000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-1070000	USD
	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	-2263000	USD
	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	-10800000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	44878000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	43661000	USD
	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	5955000	USD
	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	2962000	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	3893000	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-1748000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-9717000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-15856000	USD
	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	213000	USD
	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	-409000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	28064000	USD
	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	34142000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	417898000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	316387000	USD
CY2018Q3	us-gaap	Billed Contract Receivables BilledContractReceivables	77239000	USD
CY2017Q4	us-gaap	Billed Contract Receivables BilledContractReceivables	76760000	USD
CY2018Q3	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	240538000	USD
CY2017Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	194331000	USD
CY2018Q3	us-gaap	Other Receivables Gross Current OtherReceivablesGrossCurrent	10503000	USD
CY2017Q4	us-gaap	Other Receivables Gross Current OtherReceivablesGrossCurrent	12310000	USD
CY2018Q3	seic	Receivables Gross Current ReceivablesGrossCurrent	328280000	USD
CY2017Q4	seic	Receivables Gross Current ReceivablesGrossCurrent	283401000	USD
CY2018Q3	seic	Allowancefor Doubtful Receivables AllowanceforDoubtfulReceivables	666000	USD
CY2017Q4	seic	Allowancefor Doubtful Receivables AllowanceforDoubtfulReceivables	695000	USD
CY2018Q3	us-gaap	Receivables Net Current ReceivablesNetCurrent	327614000	USD
CY2017Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	282706000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	477003000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	456383000	USD
CY2018Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	331138000	USD
CY2017Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	309955000	USD
CY2018Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	145865000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	146428000	USD
	us-gaap	Depreciation Nonproduction DepreciationNonproduction	21515000	USD
	us-gaap	Depreciation Nonproduction DepreciationNonproduction	20347000	USD
CY2018Q3	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	68371000	USD
CY2017Q4	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	88960000	USD
CY2018Q3	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	28322000	USD
CY2017Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	29658000	USD
CY2018Q3	seic	Accrued Sub Advisory Distribution And Other Asset Management Fees Current AccruedSubAdvisoryDistributionAndOtherAssetManagementFeesCurrent	49452000	USD
CY2017Q4	seic	Accrued Sub Advisory Distribution And Other Asset Management Fees Current AccruedSubAdvisoryDistributionAndOtherAssetManagementFeesCurrent	42365000	USD
CY2018Q3	us-gaap	Dividends Payable Current DividendsPayableCurrent	0	USD
CY2017Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	47179000	USD
CY2018Q3	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	11164000	USD
CY2017Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	5583000	USD
CY2018Q3	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	50366000	USD
CY2017Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	51313000	USD
CY2018Q3	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	207675000	USD
CY2017Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	265058000	USD
CY2018Q3	us-gaap	Available For Sale Securities Equity Securities AvailableForSaleSecuritiesEquitySecurities	11326000	USD
CY2018Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	72972000	USD
CY2018Q3	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	28945000	USD
CY2018Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	5736000	USD
CY2018Q3	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	118979000	USD
CY2017Q4	us-gaap	Available For Sale Securities Equity Securities AvailableForSaleSecuritiesEquitySecurities	11250000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	76733000	USD
CY2017Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	21526000	USD
CY2017Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	6034000	USD
CY2017Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	115543000	USD
CY2018Q3	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	86544000	USD
CY2018Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	759000	USD
CY2018Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	3005000	USD
CY2018Q3	us-gaap	Available For Sale Securities AvailableForSaleSecurities	84298000	USD
CY2017Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	88570000	USD
CY2017Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	568000	USD
CY2017Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1155000	USD
CY2017Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	87983000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-2080000	USD
CY2018Q3	seic	Accumulated Other Comprehensive Income Loss Debt Securities Available For Sale Securities Adjustment Tax AccumulatedOtherComprehensiveIncomeLossDebtSecuritiesAvailableForSaleSecuritiesAdjustmentTax	-621000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-779000	USD
CY2017Q4	seic	Accumulated Other Comprehensive Income Loss Debt Securities Available For Sale Securities Adjustment Tax AccumulatedOtherComprehensiveIncomeLossDebtSecuritiesAvailableForSaleSecuritiesAdjustmentTax	-233000	USD
	seic	Debt Securities Available For Sale And Equity Securities Fnni Realized Gain DebtSecuritiesAvailableForSaleAndEquitySecuritiesFNNIRealizedGain	1031000	USD
	seic	Debt Securities Available For Sale And Equity Securities Fnni Realized Loss DebtSecuritiesAvailableForSaleAndEquitySecuritiesFNNIRealizedLoss	1520000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	428000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	706000	USD
CY2018Q3	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	28945000	USD
CY2017Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	21526000	USD
CY2018Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	5878000	USD
CY2017Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	7088000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	16396000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	19527000	USD
CY2018Q3	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1311000	USD
CY2017Q3	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	2517000	USD
	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	3556000	USD
	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6859000	USD
CY2018Q3	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	4567000	USD
CY2017Q3	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	4571000	USD
	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	12840000	USD
	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	12668000	USD
CY2018Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	47131000	USD
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	123365000	USD
CY2018Q3	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	247517000	USD
CY2018Q3	us-gaap	Share Price SharePrice	61.10
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	29.60
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	14040000	shares
CY2018Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	7857000	shares
CY2018Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	47139000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	44264000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-8923000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	32000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-8955000	USD
CY2018Q3	us-gaap	Revenues Revenues	408682000	USD
CY2018Q3	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	281320000	USD
CY2018Q3	us-gaap	Gross Profit GrossProfit	127362000	USD
CY2017Q3	us-gaap	Revenues Revenues	386018000	USD
CY2017Q3	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	271288000	USD
CY2017Q3	us-gaap	Gross Profit GrossProfit	114730000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	112420000	USD
CY2017Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	99237000	USD
CY2018Q3	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	17739000	USD
CY2017Q3	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	25352000	USD
CY2018Q3	us-gaap	Depreciation Depreciation	7255000	USD
CY2017Q3	us-gaap	Depreciation Depreciation	6948000	USD
CY2018Q3	us-gaap	Adjustment For Amortization AdjustmentForAmortization	12405000	USD
CY2017Q3	us-gaap	Adjustment For Amortization AdjustmentForAmortization	13745000	USD
	us-gaap	Revenues Revenues	1219110000	USD
	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	833686000	USD
	us-gaap	Gross Profit GrossProfit	385424000	USD
	us-gaap	Revenues Revenues	1118333000	USD
	us-gaap	Operating Costs And Expenses OperatingCostsAndExpenses	782522000	USD
	us-gaap	Gross Profit GrossProfit	335811000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	339026000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	289981000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	55023000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	68891000	USD
	us-gaap	Depreciation Depreciation	21515000	USD
	us-gaap	Depreciation Depreciation	20347000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	36420000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	38332000	USD
CY2018Q3	seic	Gross Liability For Unrecognized Tax Benefits Exclusive Of Interest And Penalties GrossLiabilityForUnrecognizedTaxBenefitsExclusiveOfInterestAndPenalties	14342000	USD
CY2017Q4	seic	Gross Liability For Unrecognized Tax Benefits Exclusive Of Interest And Penalties GrossLiabilityForUnrecognizedTaxBenefitsExclusiveOfInterestAndPenalties	14480000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	13670000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	13737000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1366000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1175000	USD
CY2018Q3	seic	Gross Liability For Unrecognized Tax Benefits Exclusive Of Interest And Penalties GrossLiabilityForUnrecognizedTaxBenefitsExclusiveOfInterestAndPenalties	14342000	USD
CY2017Q4	seic	Gross Liability For Unrecognized Tax Benefits Exclusive Of Interest And Penalties GrossLiabilityForUnrecognizedTaxBenefitsExclusiveOfInterestAndPenalties	14480000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1366000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	1175000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15708000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15655000	USD
CY2018Q3	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	1398000	USD
CY2017Q4	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	3275000	USD
CY2018Q3	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	14310000	USD
CY2017Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	12380000	USD
CY2018Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15708000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15655000	USD
CY2018Q3	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2017Q3	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2018Q3	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.023
CY2017Q3	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.017
	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.023
	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.017
CY2018Q3	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.002
CY2017Q3	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.010
	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.002
	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.010
CY2018Q3	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.014
CY2017Q3	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.045
	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.048
	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.039
CY2018Q3	seic	Effective Income Tax Rate Reconciliation Expiration Of Statute Of Limitations Percent EffectiveIncomeTaxRateReconciliationExpirationOfStatuteOfLimitationsPercent	-0.010
CY2017Q3	seic	Effective Income Tax Rate Reconciliation Expiration Of Statute Of Limitations Percent EffectiveIncomeTaxRateReconciliationExpirationOfStatuteOfLimitationsPercent	-0.026
	seic	Effective Income Tax Rate Reconciliation Expiration Of Statute Of Limitations Percent EffectiveIncomeTaxRateReconciliationExpirationOfStatuteOfLimitationsPercent	-0.003
	seic	Effective Income Tax Rate Reconciliation Expiration Of Statute Of Limitations Percent EffectiveIncomeTaxRateReconciliationExpirationOfStatuteOfLimitationsPercent	-0.009
CY2018Q3	seic	Effective Income Tax Rate Reconciliation Provision To Return Adjustment Percent EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentPercent	-0.023
CY2017Q3	seic	Effective Income Tax Rate Reconciliation Provision To Return Adjustment Percent EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentPercent	0
	seic	Effective Income Tax Rate Reconciliation Provision To Return Adjustment Percent EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentPercent	-0.008
	seic	Effective Income Tax Rate Reconciliation Provision To Return Adjustment Percent EffectiveIncomeTaxRateReconciliationProvisionToReturnAdjustmentPercent	0
CY2018Q3	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.002
CY2017Q3	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.009
	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0
	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.007
CY2018Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.186
CY2017Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.277
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.172
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.302
CY2018Q3	seic	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Transition Tax For Accumulated Foreign Earnings Provisional Liability TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalLiability	10711000	USD
	seic	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Transition Tax For Accumulated Foreign Earnings Payment TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsPayment	1000000	USD
	seic	Effective Income Tax Reconciliation Previous Overpayment Of Taxes Benefit EffectiveIncomeTaxReconciliationPreviousOverpaymentOfTaxesBenefit	8941000	USD
CY2018Q3	seic	Tax Cuts And Jobs Actof2017 Transition Tax For Accumulated Foreign Earnings Liability Noncurrent TaxCutsAndJobsActof2017TransitionTaxForAccumulatedForeignEarningsLiabilityNoncurrent	770000	USD
CY2018Q3	us-gaap	Loss Contingency Pending Claims Number LossContingencyPendingClaimsNumber	7	Lawsuit
CY2017Q4	us-gaap	Goodwill Goodwill	52990000	USD
	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	11499000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	64489000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	36760000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	30130000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	4169000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1552000	USD
CY2018Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	32591000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	28578000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2617000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	857000	USD
CY2018Q3	us-gaap	Revenues Revenues	408682000	USD
CY2018Q3	us-gaap	Revenues Revenues	408682000	USD
	us-gaap	Revenues Revenues	1219110000	USD
	us-gaap	Revenues Revenues	1219110000	USD
CY2018Q3	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	22104000	USD
CY2018Q3	seic	Capitalized Contract Cost Amount Capitalized During Period CapitalizedContractCostAmountCapitalizedDuringPeriod	1400000	USD
	seic	Capitalized Contract Cost Amount Capitalized During Period CapitalizedContractCostAmountCapitalizedDuringPeriod	5483000	USD
CY2018Q3	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	819000	USD
	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2020000	USD
	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD

Files In Submission

Name	View Source	Status
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0000350894-18-000053-index.html	Edgar Link	pending
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seic-20180930.xsd	Edgar Link	pending
seic-20180930_cal.xml	Edgar Link	unprocessable
seic-20180930_def.xml	Edgar Link	unprocessable
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seic-9301810q.htm	Edgar Link	pending
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seic-9301810qex32.htm	Edgar Link	pending
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seic-earningsreleaseex.htm	Edgar Link	pending
seiexhibit991logoa18.jpg	Edgar Link	pending
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$SEIC
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2018 Q4 Form 10-Q Financial Statement

#000035089418000053 Filed on October 25, 2018

Income Statement

Balance Sheet

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Facts In Submission

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$SEIC SEI INVESTMENTS CO Stock $seic

2018 Q4 Form 10-Q Financial Statement

#000035089418000053 Filed on October 25, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SEIC
SEI INVESTMENTS CO Stock $seic