Capital Conservation Buffer Percentage, at Beginning Stage

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- Definition

Capital Conservation Buffer Percentage, at Fully Phased-in Stage

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No definition available.

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- Definition

Capital Conservation Buffer, Phase-in Period

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- Definition

Capital Securities Qualified As Tier One Capital

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- Definition

Common Equity Tier One Capital Required To Be Well Capitalized To Risk Weighted Assets

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No definition available.

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- Definition

Increase (Decrease) in Capital to Risk Weighted Assets

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No definition available.

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- Definition

Increase (Decrease) in Tier One Common Equity to Average Assets

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No definition available.

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- Definition

Increase (Decrease) in Tier One Risk Based Capital to Risk Weighted Assets

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No definition available.

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- Definition

Risk-Based Capital Ratio in Excess of Fully Phased-in Capital Conservation Buffer, Percentage

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No definition available.

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- Definition

Risk-Based Capital Ratio in Excess of Minimum Requirement for Capital Adequacy Purposes, Percentage

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No definition available.

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- Definition

The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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- Definition

The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Regulatory Matters - Additional Information (Detail)	12 Months Ended
Regulatory Matters - Additional Information (Detail)	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016	Dec. 31, 2014
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of capital securities qualified as Tier I		25.00%		100.00%
Capital conservation buffer, phase-in period	5 years
Capital conservation buffer, percentage at the beginning stage	0.625%
Capital conservation buffer, percentage fully phased in 2019	2.50%
Exceeding percentage of Risk-based capital ratio above the minimum requirement for capital adequacy purposes	4.12%
Exceeding percentage of Risk-based capital ratio above the fully-phased in capital conservation buffer	1.62%
Minimum leverage capital ratio to be categorized as well capitalized	5.00%
Minimum Tier 1 risk based capital ratio to be categorized as well capitalized	8.00%
Minimum total risk based capital ratio to be categorized as well capitalized	10.00%
Minimum Common equity Tier 1 risk-based capital ratio	6.50%
Increase decrease in total regulatory capital, common equity, Tier 1 ratio		(0.54%)
Increase decrease in total regulatory capital, risk-based capital, Tier 1 ratio		(0.56%)
Increase decrease in total regulatory capital, risk-based capital, total ratio		(0.62%)
New York Community Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Increase decrease in total regulatory capital, common equity, Tier 1 ratio		(0.57%)
Increase decrease in total regulatory capital, risk-based capital, Tier 1 ratio		(0.57%)
Increase decrease in total regulatory capital, risk-based capital, total ratio		(0.59%)
New York Commercial Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Increase decrease in total regulatory capital, common equity, Tier 1 ratio		(0.72%)
Increase decrease in total regulatory capital, risk-based capital, Tier 1 ratio		(0.72%)
Increase decrease in total regulatory capital, risk-based capital, total ratio		(0.76%)
Multi-Family
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum total risk based capital ratio to be categorized as well capitalized			100.00%
Scenario, Previously Reported \| Multi-Family
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum total risk based capital ratio to be categorized as well capitalized			50.00%