Earnings Per Share (EPS Components) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Summary of earnings per share
Net income	$ 9,460us-gaap_NetIncomeLoss	$ 13,383us-gaap_NetIncomeLoss
Weighted Average Shares (in shares)
BASIC SHARES	24,959,865	23,819,065
EFFECT OF DILUTIVE SECURITIES	80,215	100,173
DILUTIVE SHARES	25,040,080	23,919,238
NET INCOME PER SHARE (in dollars per share)
BASIC EPS	$ 0.38us-gaap_EarningsPerShareBasic	$ 0.56us-gaap_EarningsPerShareBasic
EFFECT OF DILUTIVE SECURITIES	$ 0.00indb_EffectOfDilutiveShares	$ 0.00indb_EffectOfDilutiveShares
DILUTIVE EPS	$ 0.38us-gaap_EarningsPerShareDiluted	$ 0.56us-gaap_EarningsPerShareDiluted

Effect of dilutive shares.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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 sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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