v3.10.0.1

Stock Incentive Plans - Stock Options Outstanding (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Number of Options
Options outstanding at the beginning of the period (in shares)	1,721,978
Granted (in shares)	175,501
Exercised (in shares)	(493,984)
Expired (in shares)	(2,362)
Forfeited or cancelled (in shares)	(28,939)
Options outstanding at the end of the period (in shares)	1,372,194	1,721,978
Options exercisable at end of the period (in shares)	887,401
Weighted Average Exercise Price
Options outstanding at the beginning of the period (in dollars per share)	$ 29.10
Granted (in dollars per share)	41.26
Exercised (in dollars per share)	26.35
Expired (in dollars per share)	32.99
Forfeited or cancelled (in dollars per share)	31.63
Options outstanding at the end of the period (in dollars per share)	31.58	$ 29.10
Options exercisable at end of the period (in dollars per share)	$ 28.68
Weighted Average Remaining Contractual Term (in years)
Options outstanding	5 years 8 months 15 days	5 years 2 months 10 days
Options exercisable at end of the period	4 years 6 months 18 days
Aggregate Intrinsic Value (in thousands)
Options outstanding at the end of the period	$ 12,327
Options exercisable at the end of the period	$ 10,137

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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MB FINANCIAL INC /MD 10-K