This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

Name:	cse_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetNetRealizedAndUnrealizedGainsLosses
Namespace Prefix:	cse
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents total unrealized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ Details

Name:	cse_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetUnrealizedGainAndLosses
Namespace Prefix:	cse
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents total unrealized gains or losses for the period, arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ Details

Name:	cse_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetUnrealizedGainsLosses
Namespace Prefix:	cse
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis asset unrealized gains (losses) relating to assets.

+ Details

Name:	cse_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetUnrealizedGainsLossesRelatingToAssets
Namespace Prefix:	cse
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Realized and unrealized gains and losses on Level 3 assets income statement location.

+ Details

Name:	cse_RealizedAndUnrealizedGainsAndLossesOnLevelThreeAssetsIncomeStatementLocationAbstract
Namespace Prefix:	cse
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncome
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Fair Value Measurements (Details 1) (USD $) In Thousands	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended		3 Months Ended		6 Months Ended				6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
Fair Value Measurements (Details 1) (USD $) In Thousands	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011 Interest Income [Member]	Jun. 30, 2010 Interest Income [Member]	Jun. 30, 2011 Interest Income [Member]	Jun. 30, 2010 Interest Income [Member]	Jun. 30, 2011 Gain (Loss) on Investments, Net [Member]	Jun. 30, 2010 Gain (Loss) on Investments, Net [Member]	Jun. 30, 2011 Gain (Loss) on Investments, Net [Member]	Jun. 30, 2010 Gain (Loss) on Investments, Net [Member]	Jun. 30, 2011 Collateralized loan obligation Available-for-sale Securities [Member]	Jun. 30, 2011 Collateralized loan obligation Available-for-sale Securities [Member]	Jun. 30, 2010 Collateralized loan obligation Available-for-sale Securities [Member]	Jun. 30, 2011 Corporate debt [Member] Available-for-sale Securities [Member]	Jun. 30, 2010 Corporate debt [Member] Available-for-sale Securities [Member]	Jun. 30, 2011 Corporate debt [Member] Available-for-sale Securities [Member]	Jun. 30, 2010 Corporate debt [Member] Available-for-sale Securities [Member]	Jun. 30, 2011 Municipal Bonds [Member] Available-for-sale Securities [Member]	Mar. 31, 2011 Municipal Bonds [Member] Available-for-sale Securities [Member]	Jun. 30, 2010 Non-agency MBS [Member] Available-for-sale Securities [Member]	Mar. 31, 2010 Non-agency MBS [Member] Available-for-sale Securities [Member]	Jun. 30, 2011 Available-for-sale Securities [Member]	Jun. 30, 2010 Available-for-sale Securities [Member]	Jun. 30, 2011 Available-for-sale Securities [Member]	Jun. 30, 2010 Available-for-sale Securities [Member]	Jun. 30, 2011 Warrants [Member]	Jun. 30, 2010 Warrants [Member]	Jun. 30, 2011 Warrants [Member]	Jun. 30, 2010 Warrants [Member]	Jun. 30, 2011 Corporate debt [Member]	Jun. 30, 2011 Collateralized loan obligation	Jun. 30, 2011 Municipal Bonds [Member]
Assets
Beginning balance	$ 21,384	$ 5,637	$ 12,486	$ 7,236									$ 17,931	$ 12,249	$ 1,326	$ 0	$ 4,365	$ 15	$ 4,457	$ 0	$ 3,235	$ 61	$ 28	$ 21,166	$ 4,393	$ 12,264	$ 5,844	$ 218	$ 1,244	$ 222	$ 1,392
Included in income	682	(492)	15,541	53	690	68	3,746	159	(8)	(560)	11,795	(106)	690	17,036	636		68		125	(1,496)				690	68	15,540	761	(8)	(560)	1	(708)
Included in other comprehensive income, net	1,825	339	10,146	(118)									1,825	10,161	(308)		339	(15)	190					1,825	339	10,146	(118)
Total realized and unrealized gains (losses)	2,507	(153)	25,687	(65)									2,515	27,197	328		407	(15)	315	(1,496)				2,515	407	25,686	643	(8)	(560)	1	(708)
Acquisitions	717		5,448													717		717		4,731				717		5,448
Sales			(19,013)											(19,000)					(1,654)			(61)				(19,000)	(1,715)			(14)
Total acquisitions, sales and settlements	717		(13,565)	(1,715)										(19,000)	(1,654)	717		717		4,731		(61)		717		(13,552)	(1,715)			(14)
Ending balance	24,608	5,456	24,608	5,456									20,446	20,446	0	717	4,772	717	4,772	3,235	3,235	28	28	24,398	4,800	24,398	4,800	210	684	210	684
Unrealized gains (losses)	682	(492)	682	(492)									690	690		0	68	0	68	0		0		690	68	690	68	(8)	(560)	(8)	(560)
Unrealized gains and losses	843	(583)	843	(583)											0		125		125			0		856	68	856	68	(13)	(708)	(13)	(708)	0	2,352	(1,496)
Realized and unrealized gains and losses on Level 3 assets
Total gains (losses) included in earnings for the period	682	(492)	15,541	53	690	68	3,746	159	(8)	(560)	11,795	(106)	690	17,036	636		68		125	(1,496)				690	68	15,540	761	(8)	(560)	1	(708)
Unrealized gains (losses) relating to assets still held at reporting date					$ 690	$ 68	$ 2,347	$ 125	$ (8)	$ (560)	$ (1,504)	$ (708)