XML 76 R58.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Note 4 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Securities available-for-sale, amortized cost | $ 1,336,345 | $ 1,317,012
Securities available-for-sale, gross unrealized gains | 13,965 | 12,301
Securities available-for-sale, gross unrealized losses | 16,684 | 14,968
Securities available-for-sale | 1,333,626 | 1,314,345
US Treasury Securities [Member] |  |
Securities available-for-sale, amortized cost | 249,877 | 489,839
Securities available-for-sale, gross unrealized gains |  | 35
Securities available-for-sale, gross unrealized losses | 357 | 857
Securities available-for-sale | 249,520 | 489,017
US Government Corporations and Agencies Securities [Member] |  |
Securities available-for-sale, amortized cost | 9,047 |
Securities available-for-sale, gross unrealized gains | 11 |
Securities available-for-sale, gross unrealized losses | 70 |
Securities available-for-sale | 8,988 |
US Government-sponsored Enterprises Debt Securities [Member] |  |
Securities available-for-sale, amortized cost | 400,000 | 400,000
Securities available-for-sale, gross unrealized gains |  |
Securities available-for-sale, gross unrealized losses | 9,664 | 9,669
Securities available-for-sale | 390,336 | 390,331
Collateralized Mortgage Backed Securities [Member] |  |
Securities available-for-sale, amortized cost | 577,987 | 339,241
Securities available-for-sale, gross unrealized gains | 241 | 309
Securities available-for-sale, gross unrealized losses | 6,259 | 3,290
Securities available-for-sale | 571,969 | 336,260
US States and Political Subdivisions Debt Securities [Member] |  |
Securities available-for-sale, amortized cost | 1,944 |
Securities available-for-sale, gross unrealized gains |  |
Securities available-for-sale, gross unrealized losses | 30 |
Securities available-for-sale | 1,914 |
Collateralized Mortgage Obligations [Member] |  |
Securities available-for-sale, amortized cost | 1,533 | 48
Securities available-for-sale, gross unrealized gains |  |
Securities available-for-sale, gross unrealized losses | 17 | 20
Securities available-for-sale | 1,516 | 28
Corporate Debt Securities [Member] |  |
Securities available-for-sale, amortized cost | 80,007 | 74,965
Securities available-for-sale, gross unrealized gains | 1,291 | 247
Securities available-for-sale, gross unrealized losses | 17 | 862
Securities available-for-sale | 81,281 | 74,350
Mutual Funds [Member] |  |
Securities available-for-sale, amortized cost | 6,500 | 6,500
Securities available-for-sale, gross unrealized gains |  |
Securities available-for-sale, gross unrealized losses | 270 | 270
Securities available-for-sale | 6,230 | 6,230
Preferred Stock of Government Sponsored Entities [Member] |  |
Securities available-for-sale, amortized cost | 5,842 | 2,811
Securities available-for-sale, gross unrealized gains | 4,260 | 4,497
Securities available-for-sale, gross unrealized losses |  |
Securities available-for-sale | 10,102 | 7,308
Other Equity Securities [Member] |  |
Securities available-for-sale, amortized cost | 3,608 | 3,608
Securities available-for-sale, gross unrealized gains | 8,162 | 7,213
Securities available-for-sale, gross unrealized losses |  |
Securities available-for-sale | $ 11,770 | $ 10,821

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CollateralizedMortgageObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=caty_MutualFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=caty_PreferredStockOfGovernmentSponsoredEntitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=caty_OtherEquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |