This item represents the maturity term at inception for derivative instruments.

No definition available.

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- Definition

The increase (decrease) in fair value.

+ References

No definition available.

+ Details

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- Definition

Net accrued on interest rate swaps.

+ References

No definition available.

+ Details

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- Details

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- Definition

The sum of spot and forward contract notional amount.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The average percentage points added to the reference rate to compute the variable rate on the group of interest rate derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Average variable interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13, 16

-Article 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Details

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- Details

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Note 14 - Financial Derivatives (Details) (USD $)	3 Months Ended		1 Months Ended	12 Months Ended	1 Months Ended
Note 14 - Financial Derivatives (Details) (USD $)	Mar. 31, 2015	Mar. 31, 2014	May 31, 2014	Dec. 31, 2014	Jun. 30, 2014	Oct. 31, 2014
Note 14 - Financial Derivatives (Details) [Line Items]
Junior Subordinated Notes			$ 119,100,000us-gaap_JuniorSubordinatedNotes
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(1,588,000)
Net Accrued on Interest Rate Swaps		0caty_NetAccruedOnInterestRateSwaps
Interest Expense [Member] \| Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Net Accrued on Interest Rate Swaps	703,000
Interest Income [Member] \| Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Net Accrued on Interest Rate Swaps	683,000
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Derivative Asset, Number of Instruments Held			5
Derivative, Notional Amount	119,100,000		119,100,000
Derivative, Original Maturity			10 years
Derivative, Average Fixed Interest Rate			2.61%
Derivative, Average Variable Interest Rate			0.27%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax				(4,000,000)
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Minimum [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Derivative, Original Maturity					4 years
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Maximum [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Derivative, Original Maturity					8 years
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Derivative, Notional Amount	180,400,000				148,100,000	34,900,000
Derivative, Average Fixed Interest Rate	4.60%
Derivative, Average Variable Interest Rate	3.10%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(1,700,000)
Derivative Liability, Number of Instruments Held					10	4
Derivative, Average Basis Spread on Variable Rate	2.92%
Positive Fair Value Member
Note 14 - Financial Derivatives (Details) [Line Items]
Sum of Spot and Forward Contract Notional Amount	127,200,000			167,000,000
Increase (Decrease) in Fair Value	1,600,000			1,900,000
Negative Fair Value Member
Note 14 - Financial Derivatives (Details) [Line Items]
Sum of Spot and Forward Contract Notional Amount	158,300,000			178,900,000
Increase (Decrease) in Fair Value	(5,000,000)			(5,000,000)
Cash [Member]
Note 14 - Financial Derivatives (Details) [Line Items]
Collateral Already Posted, Aggregate Fair Value	$ 11,400,000