Regulatory Requirements and Restrictions (Schedule of Compliance with Regulatory Capital Requirements Under Banking Regulations) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital	$ 2,143,108	$ 1,937,480
Tier One Leverage Capital to Average Assets	9.35%	10.70%
Tier One Leverage Capital Required for Capital Adequacy	$ 917,207	$ 725,784
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Common Equity Tier One Risk Based Capital	$ 2,143,108
Common Equity Tier One Risk Based Capital to Risk Weighted Assets	12.58%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized	$ 1,107,156
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy	$ 766,492
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%
Tier One Risk Based Capital	$ 2,143,108	$ 1,937,480
Tier One Risk Based Capital to Risk Weighted Assets	12.58%	15.45%
Tier One Risk Based Capital Required to be Well Capitalized	$ 1,362,653	$ 752,257
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	6.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	$ 1,021,990	$ 501,505
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	4.00%
Capital	$ 2,274,910	$ 2,039,523
Capital to Risk Weighted Assets	13.36%	16.27%
Capital Required to be Well Capitalized	$ 1,703,317	$ 1,253,761
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Capital Required to be Well Capitalized to Risk Weighted Assets	$ 1,362,653	$ 1,003,009
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
BankUnited [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital	$ 2,377,689	$ 1,636,481
Tier One Leverage Capital to Average Assets	10.41%	9.10%
Tier One Leverage Capital Required to be Well Capitalized	$ 1,141,845	$ 898,708
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%
Tier One Leverage Capital Required for Capital Adequacy	$ 913,476	$ 718,967
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Common Equity Tier One Risk Based Capital	$ 2,377,689
Common Equity Tier One Risk Based Capital to Risk Weighted Assets	14.04%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized	$ 1,100,455
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy	$ 761,854
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%
Tier One Risk Based Capital	$ 2,377,689	$ 1,636,481
Tier One Risk Based Capital to Risk Weighted Assets	14.04%	13.18%
Tier One Risk Based Capital Required to be Well Capitalized	$ 1,354,406	$ 744,754
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	6.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	$ 1,015,805	$ 496,502
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	4.00%
Capital	$ 2,507,430	$ 1,736,076
Capital to Risk Weighted Assets	14.81%	13.99%
Capital Required to be Well Capitalized	$ 1,693,008	$ 1,241,256
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Capital Required to be Well Capitalized to Risk Weighted Assets	$ 1,354,406	$ 993,005
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%

Common Equity Tier One Risk Based Capital

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Common Equity Tier One Risk Based Capital Required for Capital Adequacy

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Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets

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Common Equity Tier One Risk Based Capital Required to be Well Capitalized

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Common Equity Tier One Risk Based Capital to Risk Weighted Assets

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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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.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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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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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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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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Tier 1 capital divided by risk weighted assets as defined by regulations.

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