Schedule of Actual Capital Amounts and Ratios and Selected Minimum Regulatory Thresholds (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Total risk-based capital:
Actual Amount	$ 924,408	$ 897,769
Actual Ratio	15.40%	16.20%
Adequately Capitalized Amount	$ 481,244	$ 444,685
Adequately Capitalized Ratio	8.00%	8.00%
Well Capitalized Amount	$ 601,555	$ 555,856
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 835,198	$ 807,229
Actual Ratio	13.90%	14.50%
Adequately Capitalized Amount	$ 360,933	$ 222,343
Adequately Capitalized Ratio	6.00%	4.00%
Well Capitalized Amount	$ 481,244	$ 333,514
Well Capitalized Ratio	8.00%	6.00%
Common equity tier one risk-based capital:
Actual Amount	$ 755,198
Actual Ratio	12.60%
Adequately Capitalized Amount	$ 270,700
Adequately Capitalized Ratio	4.50%
Well Capitalized Amount	$ 391,011
Well Capitalized Ratio	6.50%
Leverage capital ratio:
Actual Amount	$ 835,198
Actual Ratio	10.10%	9.60%
Adequately Capitalized Amount	$ 330,350	$ 335,897
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 412,938	$ 419,871
Well Capitalized Ratio	5.00%	5.00%
FIB
Total risk-based capital:
Actual Amount	$ 857,522	$ 832,907
Actual Ratio	14.30%	15.10%
Adequately Capitalized Amount	$ 479,416	$ 442,468
Adequately Capitalized Ratio	8.00%	8.00%
Well Capitalized Amount	$ 599,270	$ 553,085
Well Capitalized Ratio	10.00%	10.00%
Tier 1 risk-based capital:
Actual Amount	$ 776,594	$ 754,708
Actual Ratio	13.00%	13.70%
Adequately Capitalized Amount	$ 359,562	$ 221,234
Adequately Capitalized Ratio	6.00%	4.00%
Well Capitalized Amount	$ 479,416	$ 331,851
Well Capitalized Ratio	8.00%	6.00%
Common equity tier one risk-based capital:
Actual Amount	$ 776,594
Actual Ratio	13.00%
Adequately Capitalized Amount	$ 269,671
Adequately Capitalized Ratio	4.50%
Well Capitalized Amount	$ 389,525
Well Capitalized Ratio	6.50%
Leverage capital ratio:
Actual Amount	$ 776,594
Actual Ratio	9.40%	9.20%
Adequately Capitalized Amount	$ 329,180	$ 330,006
Adequately Capitalized Ratio	4.00%	4.00%
Well Capitalized Amount	$ 411,475	$ 412,507
Well Capitalized Ratio	5.00%	5.00%

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The amount of total capital as defined in the regulations.

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