Condensed Financial Statements of Parent Company (Statements of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net income	$ 21,085us-gaap_NetIncomeLoss	$ 17,260us-gaap_NetIncomeLoss	$ 10,894us-gaap_NetIncomeLoss
Stock-based compensation	811us-gaap_ShareBasedCompensation	948us-gaap_ShareBasedCompensation	1,082us-gaap_ShareBasedCompensation
Debt prepayment charge	0metr_DebtPrepaymentCharge	0metr_DebtPrepaymentCharge	140metr_DebtPrepaymentCharge
Increase (decrease) in other liabilities	138	2,947	(1,253)
(Increase) decrease in other assets	(361)	(985)	5,782
Net cash provided by (used in) operating activities	37,711	44,540	31,728
Net cash used by investing activities	(221,652)	(204,323)	(229,585)
Proceeds from common stock options exercised	932	304	0
Repayment of long-term debt	(15,800)us-gaap_RepaymentsOfLongTermDebt	(25,000)us-gaap_RepaymentsOfLongTermDebt	(8,540)us-gaap_RepaymentsOfLongTermDebt
Tax benefit on exercise of stock options	191	51	0
Cash dividends on preferred stock	(80)	(80)	(80)
Net cash (used in) provided by financing activities	181,777	148,197	199,366
Increase (decrease) in cash and cash equivalents	(2,164)	(11,586)	1,509
Cash and cash equivalents at beginning of the year	44,996
Cash and cash equivalents at end of year	42,832	44,996
Metro Bancorp, Inc.
Condensed Financial Statements, Captions [Line Items]
Net income	21,085	17,260	10,894
Amortization of financing costs	34	2	29
Stock-based compensation	811	948	1,082
Debt prepayment charge	0	0	140
Increase (decrease) in other liabilities	505	(243)	217
(Increase) decrease in other assets	745	(11)	2,625
Equity in undistributed net (income) loss of bank subsidiary	2,498	(18,386)	(13,161)
Net cash provided by (used in) operating activities	25,678	(430)	1,826
Net cash used by investing activities	(2,011)	(1,369)	(1,126)
Proceeds from common stock options exercised	932	304	0
Proceeds from issuance of common stock under stock purchase plan	77	67	44
Repayment of long-term debt	(15,800)	0	(8,540)
Tax benefit on exercise of stock options	191	51	0
Cash dividends on preferred stock	(80)	(80)	(80)
Purchase of treasury stock	(319)	0	0
Net cash (used in) provided by financing activities	(14,999)	342	(8,576)
Increase (decrease) in cash and cash equivalents	8,668	(1,457)	(7,876)
Cash and cash equivalents at beginning of the year	10,308	11,765	19,641
Cash and cash equivalents at end of year	18,976	10,308	11,765
Metro Bancorp, Inc. \| Banking Subsidiary [Member]
Condensed Financial Statements, Captions [Line Items]
Investment in bank subsidiary	$ (2,011)	$ (1,369)	$ (1,126)

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

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Amount after tax of income (loss) of subsidiary attributable to the parent entity.

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The increase (decrease) during the reporting period in other assets used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets, other noncurrent assets, or a combination of other current and noncurrent assets.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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