$CSGP
COSTAR GROUP, INC. Stock $csgp

$csgp Overview Financials Valuation SEC Filings Company Website

2011 Q4 Form 10-K Financial Statement

#000105735213000013 Filed on March 01, 2013

Income Statement

Concept	2011 Q4	2010 Q4	2010
Revenue	$66.20M	$58.20M	$226.3M
YoY Change	13.75%	6.59%	7.9%
Cost Of Revenue	$22.00M	$21.30M	$83.60M
YoY Change	3.29%	1.91%	13.43%
Gross Profit	$44.20M	$36.90M	$142.7M
YoY Change	19.78%	9.5%	4.97%
Gross Profit Margin	66.77%	63.4%	63.05%
Selling, General & Admin	$31.20M	$24.50M	$100.2M
YoY Change	27.35%	8.41%	15.47%
% of Gross Profit	70.59%	66.4%	70.26%
Research & Development	$4.600M	$4.800M	$17.35M
YoY Change	-4.17%	14.29%	24.82%
% of Gross Profit	10.41%	13.01%	12.16%
Depreciation & Amortization	$3.100M	$3.400M	$9.873M
YoY Change	-8.82%	-15.0%	-32.84%
% of Gross Profit	7.01%	9.21%	6.92%
Operating Expenses	$36.40M	$29.80M	$119.9M
YoY Change	22.15%	7.19%	15.16%
Operating Profit	$7.800M	$7.100M	$22.78M
YoY Change	9.86%	20.34%	-28.38%
Interest Expense	$200.0K	$100.0K	$0.00
YoY Change	100.0%	-50.0%	-100.0%
% of Operating Profit	2.56%	1.41%	0.0%
Other Income/Expense, Net
YoY Change
Pretax Income	$8.000M	$7.200M	$36.42M
YoY Change	11.11%	16.13%	10.04%
Income Tax	$2.800M	$3.400M	$10.22M
% Of Pretax Income	35.0%	47.22%	28.06%
Net Earnings	$5.200M	$3.800M	$13.29M
YoY Change	36.84%	5.56%	-28.94%
Net Earnings / Revenue	7.85%	6.53%	5.87%
Basic Earnings Per Share			$0.65
Diluted Earnings Per Share	$204.7K	$181.8K	$0.64
COMMON SHARES
Basic Shares Outstanding			20.33M shares
Diluted Shares Outstanding			20.71M shares

Balance Sheet

Concept	2011 Q4	2010 Q4	2010
SHORT-TERM ASSETS
Cash & Short-Term Investments	$548.8M	$210.1M	$210.1M
YoY Change	161.21%	-7.04%	-7.04%
Cash & Equivalents	$545.3M	$206.4M	$206.4M
Short-Term Investments	$3.500M	$3.700M	$3.700M
Other Short-Term Assets	$16.90M	$11.00M	$11.00M
YoY Change	53.64%	27.91%	27.91%
Inventory
Prepaid Expenses
Receivables	$16.59M	$13.10M	$13.10M
Other Receivables	$800.0K	$4.900M	$4.900M
Total Short-Term Assets	$583.2M	$239.2M	$239.2M
YoY Change	143.81%	-3.31%	-3.31%
LONG-TERM ASSETS
Property, Plant & Equipment	$37.57M	$69.90M	$69.90M
YoY Change	-46.25%	264.06%	264.06%
Goodwill	$91.78M	$79.60M
YoY Change	15.3%
Intangibles	$20.53M
YoY Change
Long-Term Investments	$24.60M	$29.20M	$29.20M
YoY Change	-15.75%	-1.68%	-1.68%
Other Assets	$13.40M	$3.000M	$3.000M
YoY Change	346.67%	-34.78%	-34.78%
Total Long-Term Assets	$187.9M	$200.4M	$200.4M
YoY Change	-6.26%	27.48%	27.48%
TOTAL ASSETS
Total Short-Term Assets	$583.2M	$239.2M	$239.2M
Total Long-Term Assets	$187.9M	$200.4M	$200.4M
Total Assets	$771.0M	$439.6M	$439.6M
YoY Change	75.39%	8.65%	8.65%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$6.010M	$3.100M	$3.100M
YoY Change	93.87%	-16.22%	-16.22%
Accrued Expenses	$12.76M	$30.90M	$30.90M
YoY Change	-58.7%	29.29%	29.29%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$0.00
YoY Change
Total Short-Term Liabilities	$61.78M	$50.90M	$50.90M
YoY Change	21.38%	16.48%	16.48%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change
Other Long-Term Liabilities	$0.00	$5.800M	$5.800M
YoY Change	-100.0%	222.22%	222.22%
Total Long-Term Liabilities	$0.00	$5.800M	$5.800M
YoY Change	-100.0%	222.22%	222.22%
TOTAL LIABILITIES
Total Short-Term Liabilities	$61.78M	$50.90M	$50.90M
Total Long-Term Liabilities	$0.00	$5.800M	$5.800M
Total Liabilities	$111.9M	$58.10M	$58.10M
YoY Change	92.53%	27.41%	27.41%
SHAREHOLDERS EQUITY
Retained Earnings	$29.68M
YoY Change
Common Stock	$254.0K
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$659.2M	$381.5M	$381.5M
YoY Change
Total Liabilities & Shareholders Equity	$771.0M	$439.6M	$439.6M
YoY Change	75.39%	8.65%	8.65%

Cashflow Statement

Concept	2011 Q4	2010 Q4	2010
OPERATING ACTIVITIES
Net Income	$5.200M	$3.800M	$13.29M
YoY Change	36.84%	5.56%	-28.94%
Depreciation, Depletion And Amortization	$3.100M	$3.400M	$9.873M
YoY Change	-8.82%	-15.0%	-32.84%
Cash From Operating Activities	$6.000M	$12.20M	$39.27M
YoY Change	-50.82%	84.85%	2.26%
INVESTING ACTIVITIES
Capital Expenditures	-$2.800M	-$4.300M	-$57.40M
YoY Change	-34.88%	19.44%	510.64%
Acquisitions			$0.00
YoY Change
Other Investing Activities	-$11.00M	$3.700M	$16.90M
YoY Change	-397.3%	1133.33%	20.71%
Cash From Investing Activities	-$13.80M	-$600.0K	-$40.50M
YoY Change	2200.0%	-81.82%	-1000.09%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$0.00
YoY Change			-100.0%
Debt Paid & Issued, Net			$0.00
YoY Change
Cash From Financing Activities	2.400M	-500.0K	$2.042M
YoY Change	-580.0%	-129.41%	-7.18%
NET CHANGE
Cash From Operating Activities	6.000M	12.20M	$39.27M
Cash From Investing Activities	-13.80M	-600.0K	-$40.50M
Cash From Financing Activities	2.400M	-500.0K	$2.042M
Net Change In Cash	-5.400M	11.10M	$807.0K
YoY Change	-148.65%	122.0%	-98.21%
FREE CASH FLOW
Cash From Operating Activities	$6.000M	$12.20M	$39.27M
Capital Expenditures	-$2.800M	-$4.300M	-$57.40M
Free Cash Flow	$8.800M	$16.50M	$96.67M
YoY Change	-46.67%	61.76%	102.24%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2012Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	6234000	USD
CY2011Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	6010000	USD
CY2012Q4	us-gaap	Accounts Payable Related Parties Current And Noncurrent AccountsPayableRelatedPartiesCurrentAndNoncurrent	-67167000	USD
CY2012Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	153125000	USD
CY2011Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	0	USD
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.00
CY2011Q4	us-gaap	Accounts Payable Related Parties Current And Noncurrent AccountsPayableRelatedPartiesCurrentAndNoncurrent	-49139000	USD
CY2011Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	16589000	USD
CY2012Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	16392000	USD
CY2012Q4	us-gaap	Accounts Receivable Related Parties AccountsReceivableRelatedParties	-73399000	USD
CY2011Q4	us-gaap	Accounts Receivable Related Parties AccountsReceivableRelatedParties	-57612000	USD
CY2012	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	293000	USD
CY2011	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	85000	USD
CY2012Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	0	USD
CY2011Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	978000	USD
CY2011Q4	us-gaap	Accrued Income Taxes Noncurrent AccruedIncomeTaxesNoncurrent	2151000	USD
CY2012Q4	us-gaap	Accrued Income Taxes Noncurrent AccruedIncomeTaxesNoncurrent	2818000	USD
CY2012Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	19002000	USD
CY2011Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	12761000	USD
CY2012Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	44744000	USD
CY2011Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	38759000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-4613000	USD
CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-5890000	USD
CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-8568000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-6518000	USD
CY2011Q4	us-gaap	Acquired Finite Lived Intangible Assets Weighted Average Useful Life AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife	P10Y
CY2011Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	637816000	USD
CY2012Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	792988000	USD
CY2011	us-gaap	Adjustment For Amortization AdjustmentForAmortization	4417000	USD
CY2010	us-gaap	Adjustment For Amortization AdjustmentForAmortization	5042000	USD
CY2012	us-gaap	Adjustment For Amortization AdjustmentForAmortization	22699000	USD
CY2010	us-gaap	Advertising Expense AdvertisingExpense	3000000	USD
CY2011	us-gaap	Advertising Expense AdvertisingExpense	2500000	USD
CY2012	us-gaap	Advertising Expense AdvertisingExpense	4400000	USD
CY2011	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	8103000	USD
CY2010	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	8306000	USD
CY2012	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12282000	USD
CY2012Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2935000	USD
CY2011Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2524000	USD
CY2012	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	1989000	USD
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CY2011	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	0	USD
CY2012	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	1989000	USD
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CY2011Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	30777000	USD
CY2012Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	23604000	USD
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CY2012Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	21156000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	0	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	580000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	21119000	USD
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CY2011Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	28099000	USD
CY2012Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	21699000	USD
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CY2012	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	0	USD
CY2012	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	0	USD
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CY2011	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	0	USD
CY2011Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	2742000	USD
CY2012Q4	us-gaap	Available For Sale Securities Gross Unrealized Losses1 AvailableForSaleSecuritiesGrossUnrealizedLosses1	2006000	USD
CY2011Q4	us-gaap	Availableforsale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses2 AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses2	0	USD
CY2012Q4	us-gaap	Availableforsale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses2 AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLosses2	0	USD
CY2011Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	64000	USD
CY2012Q4	us-gaap	Availableforsale Securities Gross Unrealized Gain AvailableforsaleSecuritiesGrossUnrealizedGain	101000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	156027000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	545280000	USD
CY2009Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	205786000	USD
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CY2011Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies	0	USD
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CY2011Q4	us-gaap	Common Stock Value CommonStockValue	254000	USD
CY2011	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	14794000	USD
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CY2012	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	11965000	USD
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CY2011	us-gaap	Cost Of Revenue CostOfRevenue	88167000	USD
CY2012	us-gaap	Cost Of Revenue CostOfRevenue	114866000	USD
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CY2010	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	7061000	USD
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CY2012	us-gaap	Investment Income Interest InvestmentIncomeInterest	526000	USD
CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-2260000	USD
CY2011	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	22779000	USD
CY2011	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	12000	USD
CY2010	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	61000	USD
CY2012	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	55000	USD
CY2011	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	25017000	USD
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CY2011	us-gaap	Investment Income Interest InvestmentIncomeInterest	798000	USD
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CY2011Q4	us-gaap	Deferred Costs DeferredCosts	918000	USD
CY2012Q4	us-gaap	Deferred Costs DeferredCosts	6622000	USD
CY2012Q4	us-gaap	Deferred Costs Current DeferredCostsCurrent	2934000	USD
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CY2012	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	15512000	USD
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CY2010	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	1673000	USD
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CY2012Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	17305000	USD
CY2011Q4	us-gaap	Deferred Revenue Current DeferredRevenueCurrent	22271000	USD
CY2012Q4	us-gaap	Deferred Revenue Current DeferredRevenueCurrent	32548000	USD
CY2011	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-2425000	USD
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CY2012Q4	us-gaap	Deferred Tax Assets Deferred Gain On Sale Leaseback Transaction DeferredTaxAssetsDeferredGainOnSaleLeasebackTransaction	12386000	USD
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CY2012Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	1220000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	1180000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	38554000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	53699000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	26721000	USD
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CY2012Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	-24815000	USD
CY2012	us-gaap	Interest Paid InterestPaid	2500000	USD
CY2011	us-gaap	Interest Paid InterestPaid	0	USD
CY2011Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	-18344000	USD
CY2012Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	-18344000	USD
CY2011Q4	us-gaap	Liabilities Liabilities	111858000	USD
CY2012Q4	us-gaap	Liabilities Liabilities	338796000	USD
CY2011Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	771035000	USD
CY2012Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1165139000	USD
CY2011Q4	us-gaap	Liabilities Current LiabilitiesCurrent	61782000	USD
CY2012Q4	us-gaap	Liabilities Current LiabilitiesCurrent	101638000	USD
CY2012Q4	us-gaap	Line Of Credit Facility Amount Outstanding LineOfCreditFacilityAmountOutstanding	0	USD
CY2012Q4	us-gaap	Long Term Debt LongTermDebt	170625000	USD
CY2012Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	17500000	USD
CY2011Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	17500000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	35000000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	21451000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	11227000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	9256000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	10224000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	0	USD
CY2011Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	6129000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	20431000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	4830000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	3987000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	4946000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	4049000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	963000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	1106000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Deferred Rent DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent	1781000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Deferred Rent DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsDeferredRent	1845000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	6007000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	5936000	USD
CY2011Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	1025000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	928000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	68024000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	11833000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	62915000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	7233000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	34071000	USD
CY2011Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	0	USD
CY2011Q4	us-gaap	Deposits Assets Noncurrent DepositsAssetsNoncurrent	2241000	USD
CY2012Q4	us-gaap	Deposits Assets Noncurrent DepositsAssetsNoncurrent	2274000	USD
CY2010	us-gaap	Depreciation Depreciation	8607000	USD
CY2012	us-gaap	Depreciation Depreciation	10053000	USD
CY2011	us-gaap	Depreciation Depreciation	8435000	USD
CY2011	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	9262000	USD
CY2012	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	10511000	USD
CY2010	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	9873000	USD
CY2010	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	674000	USD
CY2012	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	122000	USD
CY2011	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	628000	USD
CY2011	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.63
CY2010	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.65
CY2012	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.37
CY2011	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2010	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.64
CY2012	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.37
CY2011	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	44000	USD
CY2012	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	78000	USD
CY2010	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-188000	USD
CY2011Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	16695000	USD
CY2012Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	23831000	USD
CY2011	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	2541000	USD
CY2012	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	198000	USD
CY2010	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	902000	USD
CY2010	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	902000	USD
CY2012	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	198000	USD
CY2011	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	2541000	USD
CY2011	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements	2100000	USD
CY2012Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	2304000	USD
CY2011Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2010Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	3222000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	27100000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	9900000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	18900000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	20800000	USD
CY2012Q4	us-gaap	Long Term Investments LongTermInvestments	21662000	USD
CY2012Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	23500000	USD
CY2011Q4	us-gaap	Finite Lived Intangible Assets Amortization Method FiniteLivedIntangibleAssetsAmortizationMethod	125% declining balance method
CY2012Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	170632000	USD
CY2011Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	20530000	USD
CY2011	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	0	USD
CY2010	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	0	USD
CY2012	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	0	USD
CY2011	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	58362000	USD
CY2010	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	47776000	USD
CY2012	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	77154000	USD
CY2011Q4	us-gaap	Goodwill Goodwill	91784000	USD
CY2012Q4	us-gaap	Goodwill Goodwill	718078000	USD
CY2010Q4	us-gaap	Goodwill Goodwill	79602000	USD
CY2011	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	12205000	USD
CY2012	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	625174000	USD
CY2011	us-gaap	Goodwill Translation Adjustments GoodwillTranslationAdjustments	-23000	USD
CY2012	us-gaap	Goodwill Translation Adjustments GoodwillTranslationAdjustments	1120000	USD
CY2011	us-gaap	Gross Profit GrossProfit	163571000	USD
CY2010	us-gaap	Gross Profit GrossProfit	142661000	USD
CY2012	us-gaap	Gross Profit GrossProfit	235070000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	36100000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	30200000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	29100000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	36424000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	60192000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	34623000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-6600000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-13000000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-6700000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	22569000	USD
CY2010	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	23510000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	23134000	USD
CY2010	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10221000	USD
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13219000	USD
CY2011	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7913000	USD
CY2011	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	643000	USD
CY2012	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	2978000	USD
CY2010	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1657000	USD
CY2012	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-2971000	USD
CY2011	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-961000	USD
CY2010	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	-1688000	USD
CY2012	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	8097000	USD
CY2010	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	8229000	USD
CY2011	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	7899000	USD
CY2012	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	656000	USD
CY2012	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	1827000	USD
CY2011	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	2669000	USD
CY2010	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	945000	USD
CY2011	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	448000	USD
CY2011	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	0	USD
CY2010	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	0	USD
CY2012	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	5829000	USD
CY2011	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-143000	USD
CY2012	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-313000	USD
CY2010	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	289000	USD
CY2010	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	409000	USD
CY2011	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	150000	USD
CY2012	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	303000	USD
CY2010	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1372000	USD
CY2011	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-123000	USD
CY2012	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1360000	USD
CY2011	us-gaap	Income Taxes Paid IncomeTaxesPaid	19500000	USD
CY2012	us-gaap	Income Taxes Paid IncomeTaxesPaid	2600000	USD
CY2010	us-gaap	Income Taxes Paid IncomeTaxesPaid	12900000	USD
CY2012Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	5357000	USD
CY2011Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	850000	USD
CY2010	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	6746000	USD
CY2010	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	1776000	USD
CY2011	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	4573000	USD
CY2012	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-1295000	USD
CY2011	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	4334000	USD
CY2010	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	2162000	USD
CY2012	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	5787000	USD
CY2012	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1172000	USD
CY2011	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-154000	USD
CY2010	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-385000	USD
CY2010	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	-4994000	USD
CY2012	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	7400000	USD
CY2011	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	5451000	USD
CY2011	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-4000	USD
CY2010	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-70000	USD
CY2012	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-33000	USD
CY2010	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	714000	USD
CY2011	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-1042000	USD
CY2012	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	3349000	USD
CY2011Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	20530000	USD
CY2012Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	170632000	USD
CY2012	us-gaap	Interest Expense InterestExpense	4832000	USD
CY2011	us-gaap	Interest Expense InterestExpense	0	USD
CY2010	us-gaap	Interest Expense InterestExpense	0	USD
CY2010	us-gaap	Net Income Loss NetIncomeLoss	13289000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	61250000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	32812000	USD
CY2012Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	24063000	USD
CY2010	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1141000	USD
CY2011Q2	us-gaap	Loss Contingency Estimate Of Possible Loss LossContingencyEstimateOfPossibleLoss	200000	USD
CY2012	us-gaap	Nature Of Operations NatureOfOperations	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">ORGANIZATION</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">CoStar Group, Inc. (the “Company” or “CoStar”) provides information, analytics and marketing services to the commercial real estate and related business community through its comprehensive, proprietary database of commercial real estate information covering the United States (“U.S.”) and parts of the United Kingdom ("U.K.") and France, as well as its complementary online marketplace of commercial real estate listings. The Company operates within </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">two</font><font style="font-family:inherit;font-size:10pt;"> operating segments, U.S. and International, and its services are typically distributed to its clients under subscription-based license agreements that renew automatically, a majority of which have a term of </font><font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;">one year</font><font style="font-family:inherit;font-size:10pt;">.</font></div></div>
CY2010	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	2042000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	164941000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	254780000	USD
CY2010	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-40504000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-640398000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	58366000	USD
CY2010	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	39269000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	25685000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	86126000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	9915000	USD
CY2011	us-gaap	Net Income Loss NetIncomeLoss	14656000	USD
CY2012	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	operating_segments
CY2010	us-gaap	Operating Expenses OperatingExpenses	119886000	USD
CY2011	us-gaap	Operating Expenses OperatingExpenses	141800000	USD
CY2012	us-gaap	Operating Expenses OperatingExpenses	207630000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	27440000	USD
CY2010	us-gaap	Operating Income Loss OperatingIncomeLoss	22775000	USD
CY2011	us-gaap	Operating Income Loss OperatingIncomeLoss	21771000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	131589000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	14907000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	10919000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	10787000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	11756000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	12840000	USD
CY2012Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	70380000	USD
CY2011	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	13300000	USD
CY2010	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	12000000	USD
CY2012	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	16700000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	1277000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	25000	USD
CY2010	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-1064000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	2050000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	138000	USD
CY2011Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	2000000	shares
CY2011	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	113000	USD
CY2010	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-77000	USD
CY2012	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	773000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	91052000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	46308000	USD
CY2011Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	37571000	USD
CY2011Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	0	USD
CY2012Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1030000	USD
CY2012	us-gaap	Payments For Rent PaymentsForRent	882000	USD
CY2011	us-gaap	Payments For Rent PaymentsForRent	1319000	USD
CY2012	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	11546000	USD
CY2010	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	0	USD
CY2011	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	0	USD
CY2012	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	4204000	USD
CY2011	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2307000	USD
CY2010	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	2904000	USD
CY2011	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	15085000	USD
CY2010	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2012	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	640929000	USD
CY2010	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	57358000	USD
CY2012	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	14834000	USD
CY2011	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	15013000	USD
CY2012Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2011Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
CY2012Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	2000000	shares
CY2011Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2012Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2011Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2012Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2011Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	5722000	USD
CY2012Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	9560000	USD
CY2012	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2011	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	247924000	USD
CY2010	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	175000000	USD
CY2010	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2011	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	4911000	USD
CY2010	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	16854000	USD
CY2012	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	15365000	USD
CY2011Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	76330000	USD
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.40
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.40
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.40
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.022
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.009
CY2011	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.022
CY2011	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1525000	USD
CY2012	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1456000	USD
CY2010	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1471000	USD
CY2010	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4375000	USD
CY2011	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2011	us-gaap	Research And Development Expense Software Excluding Acquired In Process Cost ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost	20037000	USD
CY2012	us-gaap	Research And Development Expense Software Excluding Acquired In Process Cost ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost	32756000	USD
CY2010	us-gaap	Research And Development Expense Software Excluding Acquired In Process Cost ResearchAndDevelopmentExpenseSoftwareExcludingAcquiredInProcessCost	17350000	USD
CY2012Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	0	USD
CY2011Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	195000	USD
CY2012Q4	us-gaap	Restructuring Reserve RestructuringReserve	32000	USD
CY2011Q4	us-gaap	Restructuring Reserve RestructuringReserve	833000	USD
CY2010Q4	us-gaap	Restructuring Reserve RestructuringReserve	931000	USD
CY2012	us-gaap	Restructuring Reserve Accrual Adjustment RestructuringReserveAccrualAdjustment	75000	USD
CY2011	us-gaap	Restructuring Reserve Accrual Adjustment RestructuringReserveAccrualAdjustment	195000	USD
CY2010	us-gaap	Restructuring Reserve Accrual Adjustment RestructuringReserveAccrualAdjustment	0	USD
CY2011Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	29675000	USD
CY2012Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	39590000	USD
CY2012	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	12207000	USD
CY2012	us-gaap	Revenues Revenues	349936000	USD
CY2011	us-gaap	Revenues Revenues	251738000	USD
CY2010	us-gaap	Revenues Revenues	226260000	USD
CY2012	us-gaap	Sale Leaseback Transaction Net Proceeds SaleLeasebackTransactionNetProceeds	0	USD
CY2011	us-gaap	Sale Leaseback Transaction Net Proceeds SaleLeasebackTransactionNetProceeds	83553000	USD
CY2010	us-gaap	Sale Leaseback Transaction Net Proceeds SaleLeasebackTransactionNetProceeds	0	USD
CY2012	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	9196000	USD
CY2012	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y
CY2010	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	3722000	USD
CY2011	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	6214000	USD
CY2010	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	161000	USD
CY2012	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	84113000	USD
CY2010	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	52455000	USD
CY2011	us-gaap	Selling And Marketing Expense SellingAndMarketingExpense	61164000	USD
CY2011	us-gaap	Share Based Compensation ShareBasedCompensation	8103000	USD
CY2012	us-gaap	Share Based Compensation ShareBasedCompensation	12282000	USD
CY2010	us-gaap	Share Based Compensation ShareBasedCompensation	8306000	USD
CY2010	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.00
CY2012	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.00
CY2010	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	USD
CY2010	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	116000	USD
CY2011	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	1000	USD
CY2012	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	USD
CY2011	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	8056000	USD
CY2010	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	8270000	USD
CY2011	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y
CY2012Q4	us-gaap	Short Term Investments ShortTermInvestments	37000	USD
CY2011Q4	us-gaap	Short Term Investments ShortTermInvestments	3515000	USD
CY2012	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	137055000	USD
CY2011	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	452000	USD
CY2012	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	749000	USD
CY2010	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	360000	USD
CY2011	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	247924000	USD
CY2012	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	4204000	USD
CY2010	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	2906000	USD
CY2011	us-gaap	Stock Issued During Period Value Restricted Stock Award Forfeitures StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures	2307000	USD
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	659177000	USD
CY2012Q4	us-gaap	Stockholders Equity StockholdersEquity	826343000	USD
CY2010Q4	us-gaap	Stockholders Equity StockholdersEquity	381502000	USD
CY2009Q4	us-gaap	Stockholders Equity StockholdersEquity	359006000	USD
CY2012	us-gaap	Tax Benefit From Stock Options Exercised1 TaxBenefitFromStockOptionsExercised1	198000	USD
CY2011	us-gaap	Tax Benefit From Stock Options Exercised1 TaxBenefitFromStockOptionsExercised1	2541000	USD
CY2010	us-gaap	Tax Benefit From Stock Options Exercised1 TaxBenefitFromStockOptionsExercised1	902000	USD
CY2011Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	918000	USD
CY2012Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	9556000	USD
CY2012	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	773000	USD
CY2011	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	113000	USD
CY2010	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-77000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	69000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	61000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3909000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1766000	USD
CY2009Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1856000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3347000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	44000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	1600000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	52000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	7000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	8000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	-17000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	792000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1243000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	70000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	445000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	290000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	215000	USD
CY2010Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	184000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	75000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	31000	USD
CY2010	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	20000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	107000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	69000	USD
CY2011Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	1400000	USD
CY2012	us-gaap	Use Of Estimates UseOfEstimates	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Use of Estimates</font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.</font></div></div>
CY2012Q4	us-gaap	Valuation Allowance Amount ValuationAllowanceAmount	10490000	USD
CY2011Q4	us-gaap	Valuation Allowance Amount ValuationAllowanceAmount	5270000	USD
CY2011	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	600000	USD
CY2012	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	5200000	USD
CY2010Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2415000	USD
CY2011Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2524000	USD
CY2012Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2935000	USD
CY2009Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2863000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	1456000	USD
CY2010	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	1471000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	1525000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	0	USD
CY2012	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	475000	USD
CY2010	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	0	USD
CY2012	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	1520000	USD
CY2010	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	1919000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	1416000	USD
CY2011	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	23527000	shares
CY2010	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	20707000	shares
CY2012	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	26949000	shares
CY2011	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23131000	shares
CY2010	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	20330000	shares
CY2012	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	26533000	shares
CY2012Q4	csgp	Deferred Tax Liabilities Prepaids DeferredTaxLiabilitiesPrepaids	1433000	USD
CY2011Q4	csgp	Deferred Tax Liabilities Prepaids DeferredTaxLiabilitiesPrepaids	1054000	USD
CY2011Q4	csgp	Accumulated Other Comprehensive Income Loss Investment Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossInvestmentSecuritiesAdjustmentNetOfTax	-2678000	USD
CY2012Q1	csgp	Libor Maturity Period LiborMaturityPeriod	P1M
CY2012Q4	csgp	Accumulated Other Comprehensive Income Loss Investment Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossInvestmentSecuritiesAdjustmentNetOfTax	-1905000	USD
CY2012	csgp	Amortization Expense Capitalized Product Development Costs AmortizationExpenseCapitalizedProductDevelopmentCosts	191000	USD
CY2010	csgp	Amortization Expense Capitalized Product Development Costs AmortizationExpenseCapitalizedProductDevelopmentCosts	0	USD
CY2011	csgp	Amortization Expense Capitalized Product Development Costs AmortizationExpenseCapitalizedProductDevelopmentCosts	80000	USD
CY2012	csgp	Auction Rate Securities Variable Rate Debt Instruments Interest Rate Reset Period AuctionRateSecuritiesVariableRateDebtInstrumentsInterestRateResetPeriod	P28D
CY2011Q2	csgp	Business Acquisition Contingent Consideration Cash Payment BusinessAcquisitionContingentConsiderationCashPayment	500000	USD
CY2011Q3	csgp	Business Acquisition Contingent Consideration Cash Payment BusinessAcquisitionContingentConsiderationCashPayment	1600000	USD
CY2010	csgp	Business Acquisition Deferred Consideration Liability Reversal BusinessAcquisitionDeferredConsiderationLiabilityReversal	0	USD
CY2011	csgp	Business Acquisition Deferred Consideration Liability Reversal BusinessAcquisitionDeferredConsiderationLiabilityReversal	1207000	USD
CY2012	csgp	Business Acquisition Deferred Consideration Liability Reversal BusinessAcquisitionDeferredConsiderationLiabilityReversal	0	USD
CY2012	csgp	Change In Valuation Allowance Increase For Foreign Deferred Tax Assets ChangeInValuationAllowanceIncreaseForForeignDeferredTaxAssets	3000000	USD
CY2012	csgp	Changeinvaluationallowanceincreaserelatedtoacquisition Changeinvaluationallowanceincreaserelatedtoacquisition	2200000	USD
	csgp	Debt Issuance Legal Fees DebtIssuanceLegalFees	2300000	USD
	csgp	Debt Issuance Underwriting Fees DebtIssuanceUnderwritingFees	9200000	USD
CY2012Q1	csgp	Default Interest Rate Spread Per Annum DefaultInterestRateSpreadPerAnnum	0.02
CY2012Q4	csgp	Deferred Gain On Sale Of Building Noncurrent DeferredGainOnSaleOfBuildingNoncurrent	28809000	USD
CY2011Q4	csgp	Deferred Gain On Sale Of Building Noncurrent DeferredGainOnSaleOfBuildingNoncurrent	31333000	USD
CY2012Q4	csgp	Deferred Tax Liabilities Depreciation DeferredTaxLiabilitiesDepreciation	3676000	USD
CY2011Q4	csgp	Deferred Tax Liabilities Depreciation DeferredTaxLiabilitiesDepreciation	3546000	USD
CY2012Q4	csgp	Intangible Asset Net Book Value IntangibleAssetNetBookValue	302000	USD
CY2011Q4	csgp	Liabilities Deferred Consideration Fair Value Disclosuredeferred Consideration LiabilitiesDeferredConsiderationFairValueDisclosuredeferredConsideration	0	USD
CY2012Q4	csgp	Liabilities Deferred Consideration Fair Value Disclosuredeferred Consideration LiabilitiesDeferredConsiderationFairValueDisclosuredeferredConsideration	2304000	USD
CY2012Q1	csgp	Excess Cash Flow Payment Maturity Period Within Issuance Of Financial Statements ExcessCashFlowPaymentMaturityPeriodWithinIssuanceOfFinancialStatements	P10D
CY2012	csgp	Fair Value Liabilities Deferred Consideration Upon Acquisition FairValueLiabilitiesDeferredConsiderationUponAcquisition	2011000	USD
CY2011	csgp	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Adjustments FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityAdjustments	1207000	USD
CY2012Q1	csgp	First Excess Cash Flow Repayment Percentage FirstExcessCashFlowRepaymentPercentage	0.5
CY2010	csgp	Income Tax Reconciliation Disregarded Entity Election IncomeTaxReconciliationDisregardedEntityElection	-992000	USD
CY2011	csgp	Income Tax Reconciliation Disregarded Entity Election IncomeTaxReconciliationDisregardedEntityElection	0	USD
CY2012	csgp	Income Tax Reconciliation Disregarded Entity Election IncomeTaxReconciliationDisregardedEntityElection	0	USD
CY2012Q2	csgp	Increaseinsharesauthorized Increaseinsharesauthorized	30000000	shares
CY2011Q4	csgp	Intangible Asset Net Book Value IntangibleAssetNetBookValue	493000	USD
CY2012Q1	csgp	Maximum Debt Service Coverage Ratio MaximumDebtServiceCoverageRatio	1.5
CY2012	csgp	Maximum Original Maturity Of Highly Liquid Investments To Be Considered Cash Equivalents MaximumOriginalMaturityOfHighlyLiquidInvestmentsToBeConsideredCashEquivalents	P3M
CY2012Q1	csgp	Maximum Total Leverage Ratio After Eight Fiscal Quarters MaximumTotalLeverageRatioAfterEightFiscalQuarters	2.50
CY2012Q1	csgp	Maximum Total Leverage Ratio For Fifth Through Eighth Quarters After Closing Date MaximumTotalLeverageRatioForFifthThroughEighthQuartersAfterClosingDate	2.75
CY2012Q1	csgp	Maximum Total Leverage Ratio For Third And Fourth Quarters After Closing Date MaximumTotalLeverageRatioForThirdAndFourthQuartersAfterClosingDate	3
CY2012Q1	csgp	Maximum Total Leverage Ratio For Two Quarters After Closing MaximumTotalLeverageRatioForTwoQuartersAfterClosing	3.25
CY2012	csgp	Minimum Contractual Maturities On Underlying Securities Involved In Auction Rate Securities MinimumContractualMaturitiesOnUnderlyingSecuritiesInvolvedInAuctionRateSecurities	P20Y
CY2012	csgp	Minimum Contractual Maturity Forr Available For Sale Short Term Investments To Be Considered Current MinimumContractualMaturityForrAvailableForSaleShortTermInvestmentsToBeConsideredCurrent	P1Y
CY2012	csgp	Minimum Maturity Term At Time Of Purcahse To Be Considered Short Term Investments MinimumMaturityTermAtTimeOfPurcahseToBeConsideredShortTermInvestments	P90D
CY2012Q4	csgp	Minimum Number Of Current Litigation Matters MinimumNumberOfCurrentLitigationMatters	1	current_litigation_matters
CY2011Q2	csgp	Number Of Class Action Lawsuits Brought By Alleged Loopnet Stockholders NumberOfClassActionLawsuitsBroughtByAllegedLoopnetStockholders	3	class_action_lawsuits
CY2010	csgp	Number Of Customers Accouting For More Than Five Percent Of Revenue NumberOfCustomersAccoutingForMoreThanFivePercentOfRevenue	0	Customer
CY2012	csgp	Number Of Customers Accouting For More Than Five Percent Of Revenue NumberOfCustomersAccoutingForMoreThanFivePercentOfRevenue	0
CY2011	csgp	Number Of Customers Accouting For More Than Five Percent Of Revenue NumberOfCustomersAccoutingForMoreThanFivePercentOfRevenue	0
CY2011Q4	csgp	Number Of Distinct Intangible Asset NumberOfDistinctIntangibleAsset	1	distinct_intangible_asset
CY2011	csgp	Period Deferred Cash Payment Is Due After Closing Of Acquisition PeriodDeferredCashPaymentIsDueAfterClosingOfAcquisition	P2Y
CY2011	csgp	Proceeds From Exercise Of Stock Options And Espp ProceedsFromExerciseOfStockOptionsAndEspp	6622000	USD
CY2010	csgp	Proceeds From Exercise Of Stock Options And Espp ProceedsFromExerciseOfStockOptionsAndEspp	4044000	USD
CY2012	csgp	Proceeds From Exercise Of Stock Options And Espp ProceedsFromExerciseOfStockOptionsAndEspp	9868000	USD
CY2012	csgp	Restructuring Reserve Adjustment Sublease Revenue And Accretion RestructuringReserveAdjustmentSubleaseRevenueAndAccretion	121000	USD
CY2011	csgp	Restructuring Reserve Adjustment Sublease Revenue And Accretion RestructuringReserveAdjustmentSubleaseRevenueAndAccretion	262000	USD
CY2012Q1	csgp	Second Excess Cash Flow Repayment Percentage SecondExcessCashFlowRepaymentPercentage	0.25
CY2011Q4	csgp	Segment Reporting Segment Gross Assets SegmentReportingSegmentGrossAssets	846991000	USD
CY2012Q4	csgp	Segment Reporting Segment Gross Assets SegmentReportingSegmentGrossAssets	1256882000	USD
CY2010	csgp	Significant Customer Revenue Threshold Percent SignificantCustomerRevenueThresholdPercent	0.05
CY2012	csgp	Significant Customer Revenue Threshold Percent SignificantCustomerRevenueThresholdPercent	0.05
CY2011	csgp	Significant Customer Revenue Threshold Percent SignificantCustomerRevenueThresholdPercent	0.05
CY2012	csgp	Stock Options And Restricted Stock StockOptionsAndRestrictedStock	416000	shares
CY2010	csgp	Stock Options And Restricted Stock StockOptionsAndRestrictedStock	377000	shares
CY2011	csgp	Stock Options And Restricted Stock StockOptionsAndRestrictedStock	396000	shares
CY2012	csgp	Subscription Based Licensing Agreement Minimum Term Years SubscriptionBasedLicensingAgreementMinimumTermYears	P1Y
CY2012Q2	csgp	Term Of Consent Order Public Comment Period TermOfConsentOrderPublicCommentPeriod	P30D
CY2012Q1	csgp	Third Excess Cash Flow Repayment Percentage ThirdExcessCashFlowRepaymentPercentage	0
CY2012	csgp	Total Deferred Income Tax Per Year TotalDeferredIncomeTaxPerYear	13450000	USD
CY2011	csgp	Total Deferred Income Tax Per Year TotalDeferredIncomeTaxPerYear	-17104000	USD
CY2010	csgp	Total Deferred Income Tax Per Year TotalDeferredIncomeTaxPerYear	1675000	USD
CY2011Q4	csgp	Total Segment Liabilities TotalSegmentLiabilities	160997000	USD
CY2012Q4	csgp	Total Segment Liabilities TotalSegmentLiabilities	405963000	USD
CY2012	dei	Amendment Flag AmendmentFlag	false
CY2012	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2012	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2012	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2012
CY2012	dei	Document Period End Date DocumentPeriodEndDate	2012-12-31
CY2012	dei	Document Type DocumentType	10-K
CY2012	dei	Entity Central Index Key EntityCentralIndexKey	0001057352
CY2013Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	28339028	shares
CY2012	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2012	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2012Q2	dei	Entity Public Float EntityPublicFloat	2200000000	USD
CY2012	dei	Entity Registrant Name EntityRegistrantName	COSTAR GROUP INC
CY2012	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2012	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes

Files In Submission

Name	View Source	Status
0001057352-13-000013-index-headers.html	Edgar Link	pending
0001057352-13-000013-index.html	Edgar Link	pending
0001057352-13-000013.txt	Edgar Link	pending
0001057352-13-000013-xbrl.zip	Edgar Link	pending
csgp-20121231.xml	Edgar Link	completed
csgp-20121231.xsd	Edgar Link	pending
csgp-20121231_cal.xml	Edgar Link	unprocessable
csgp-20121231_def.xml	Edgar Link	unprocessable
csgp-20121231_lab.xml	Edgar Link	unprocessable
csgp-20121231_pre.xml	Edgar Link	unprocessable
csgp-ex1019_20121231.htm	Edgar Link	pending
csgp-ex211_20121231.htm	Edgar Link	pending
csgp-ex231_20121231.htm	Edgar Link	pending
csgp-ex311_20121231.htm	Edgar Link	pending
csgp-ex312_20121231.htm	Edgar Link	pending
csgp-ex321_20121231.htm	Edgar Link	pending
csgp-ex322_20121231.htm	Edgar Link	pending
csgp20121231-10k.htm	Edgar Link	pending
csgp2012graph.gif	Edgar Link	pending
currentcostarlogo-noreg.jpg	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xls	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
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R70.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$CSGP
COSTAR GROUP, INC. Stock $csgp

2011 Q4 Form 10-K Financial Statement

#000105735213000013 Filed on March 01, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CSGP COSTAR GROUP, INC. Stock $csgp

2011 Q4 Form 10-K Financial Statement

#000105735213000013 Filed on March 01, 2013

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CSGP
COSTAR GROUP, INC. Stock $csgp