Basis of Presentation Basis of Presentation (Policies)	6 Months Ended
Basis of Presentation Basis of Presentation (Policies)	Jun. 30, 2019
Basis Of Presentation [Abstract]
Consolidation	The consolidated financial statements include the accounts of Hope Bancorp and its wholly owned subsidiaries, principally Bank of Hope. All intercompany transactions and balances have been eliminated in consolidation. The Company has made all adjustments, that in the opinion of management, are necessary to fairly present the Company’s financial position at June 30, 2019 and December 31, 2018 and the results of operations for the three and six months ended June 30, 2019 and 2018. Certain reclassifications have been made to prior period amounts to conform to the current year presentation. The results of operations for the interim periods are not necessarily indicative of results to be anticipated for the full year.
Use of estimates	The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ significantly from those estimates.
Recent Accounting Pronouncements	g Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments”, also referred to as “CECL”. The FASB subsequently issued ASU 2018-19, ASU 2019-04, and ASU 2019-05 to provide additional clarification, implementation, codification improvements, and transition guidance related to ASU 2016-13. ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. ASU 2016-13 becomes effective for fiscal years and interim periods within those fiscal years beginning after December 15, 2019. The Company has established a CECL committee to oversee the development and implementation of ASU 2016-13. The Company is collaborating with a third party advisory team and has also engaged a software vendor to assist the Company to consolidate its models to arrive at a lifetime expected credit losses in compliance with ASU 2016-13 by the effective date. The Company is currently finalizing and documenting its methodologies and developing new processes, policies, and controls under the new guidance in preparation of performing a full end to end parallel run. Based on the Company’s initial assessment of the ASU 2016-13, the Company expects the new guidance will result in additional required allowance for loan losses which could potentially have a material impact on its consolidated financial statements and regulatory capital ratios. In January 2017, the FASB issued ASU 2017-04, “Intangibles: Goodwill and Other: Simplifying the Test for Goodwill Impairment.” ASU 2017-04 will amend and simplify current goodwill impairment testing to eliminate Step 2 from the current provisions. Under the new guidance, an entity should perform the goodwill impairment test by comparing the fair value of a reporting unit with its carrying value and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. An entity still has the option to perform the quantitative assessment for a reporting unit to determine if a quantitative impairment test is necessary. ASU 2017-04 should be adopted for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. The adoption of ASU 2017-04 is not expected to have a material impact on the Company’s consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement”. ASU 2018-13 modifies the disclosure requirements for fair value measurements by removing, modifying, or adding certain disclosures. ASU 2018-13 removes the disclosure requirement detailing the amount of and reasons for transfers between Level 1 and Level 2, and the valuation processes for Level 3 fair value measurements. In addition, ASU 2018-13 modifies the disclosure requirement for investments in certain entities that calculate net asset value. Lastly, ASU 2018-13 adds a disclosure requirement for changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 measurements. ASU 2018-13 is effective annual periods in fiscal years beginning after December 15, 2019, including interim periods within those annual periods. Early adoption is permitted upon the issuance of ASU 2018-13. The removed and modified disclosures will be adopted on a retrospective basis, and the new disclosures will be adopted on a prospective basis. The adoption of ASU 2018-13 is not expected to have a material impact on the Company’s consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, “Intangibles - Goodwill and Other - Internal Use Software (Subtopic 250-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of the FASB Emerging Issues Task Force)”. ASU 2018-15 requires an entity in a cloud computing arrangement (i.e., hosting arrangement) that is a service contract to follow the internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets or expense as incurred. Capitalized implementation costs should be presented in the same line item on the balance sheet as amounts prepaid for the hosted service, if any (generally as an “other asset”). The capitalized costs will be amortized over the term of the hosting arrangement, with the amortization expense being presented in the same income statement line item as the fees paid for the hosted service. ASU 2018-15 is effective for annual reporting periods beginning after December 15, 2019, including interim periods within those annual periods. Early adoption is permitted, including adoption in any interim period. The adoption of ASU 2018-15 is not expected to have a material impact on the Company’s consolidated financial statements. Recent Accounting Pronouncements In May 2019, the FASB issued ASU 2019-05, “Financial Instruments - Credit Losses, Topic 326.” ASU 2019-05 addresses certain stakeholders’ concerns by providing an option to irrevocably elect the fair value option for certain financial assets previously measured at amortized cost basis. For those entities, the targeted transition relief will increase comparability of financial statement information by providing an option to align measurement methodologies for similar financial assets. ASU 2016-13 allows companies to irrevocably elect, upon adoption of ASU 2016-13, the fair value option on financial instruments that (1) were previously recorded at amortized cost and (2) are within the scope of ASC 326-20 if the instruments are eligible for the fair value option under ASC 825-10. Entities are required to make this election on an instrument-by-instrument basis. The effective date for ASU 2019-05 is the same as for ASU 2016-13, or for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. The Company does not expect elect the fair value option on its financial instruments in accordance with ASU 2019-05.