Cover page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	May 13, 2020	Jun. 30, 2019
Document Information [Line Items]
Amendment Flag	true
Document Type	10-K/A
Document Annual Report	true
Document Transition Report	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Document Period End Date	Dec. 31, 2019
Entity Central Index Key	0000910073
Current Fiscal Year End Date	--12-31
Entity Registrant Name	NEW YORK COMMUNITY BANCORP INC
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Well-known Seasoned Issuer	Yes
Entity Small Business	false
Entity Voluntary Filers	No
Entity Public Float			$ 4.5
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		463,937,039
Entity Interactive Data Current	Yes
Entity File Number	1-31565
Entity Incorporation, State or Country Code	DE
City Area Code	516
Local Phone Number	683-4100
Entity Tax Identification Number	06-1377322
Entity Address, Address Line One	615 Merrick Avenue
Entity Address, City or Town	Westbury
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	11590
Amendment Description	New York Community Bancorp Inc. (the “Company”) is filing this Amendment No. 1 on Form 10-K/A (this “Amendment No. 1”) to amend the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, which was initially filed with the U.S. Securities and Exchange Commission (the “SEC”) on February 28, 2020 (the “Original 2019 Form 10-K”). The purpose of this Amendment No. 1 is to provide the Consulting Agreement between the Company and James J. Carpenter under Exhibit 10.16, which was inadvertently omitted from the Original 2019 Form 10-K. In addition, pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), new certifications by the Company’s principal executive officer and principal financial officer are filed herewith as exhibits to this Amendment No. 1 pursuant to Rule 13a-14(a) or 15d-14(a) of the Exchange Act. These certifications are attached to this Amendment No. 1 as Exhibits 31.1 and 31.2. Because no financial statements have been included in this Amendment No. 1 and this Amendment No. 1 does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4, and 5 of the certifications have been omitted. Additionally, we are not including the certificate under Section 906 of the Sarbanes-Oxley Act of 2002, as no financial statements are being filed with this Amendment No. 1. This Amendment No. 1 is an exhibit-only filing. Except as described above, this Amendment No. 1 does not modify or update in any way the financial statements or disclosures made, or any exhibits included or incorporated by reference, in the Original 2019 Form 10-K and does not reflect events occurring after the filing of the Original 2019 Form 10-K. Accordingly, this Amendment No. 1 should be read in conjunction with the Original 2019 Form 10-K and the Company’s other filings with the SEC.
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock
Trading Symbol	NYCB
Security Exchange Name	NYSE
Bifurcated Option Note Unit Securities [Member]
Document Information [Line Items]
Title of 12(b) Security	Bifurcated Option Note Unit SecuritiESSM
Trading Symbol	NYCB PU
Security Exchange Name	NYSE
Fixed to Floating Rate Series A Noncumulative Perpetual Preferred Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares each representing
Trading Symbol	NYCB PA
Security Exchange Name	NYSE