Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Employee Benefit Plans - Defined Benefit Plans - Fair Value of Assets (Details) - The Bank - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Mutual funds-fixed income
Defined Benefit Plans
Target asset allocations	40.00%
Mutual funds-equity
Defined Benefit Plans
Target asset allocations	60.00%
Cash Balance Plan
Defined Benefit Plans
Assets at Fair Value	$ 19,254	$ 16,202	$ 14,697	$ 14,084
Cash Balance Plan \| Level 1
Defined Benefit Plans
Assets at Fair Value	19,254	16,202
Cash Balance Plan \| Mutual funds-fixed income
Defined Benefit Plans
Assets at Fair Value	7,510	6,273
Cash Balance Plan \| Mutual funds-fixed income \| Level 1
Defined Benefit Plans
Assets at Fair Value	7,510	6,273
Cash Balance Plan \| Mutual funds-equity
Defined Benefit Plans
Assets at Fair Value	11,744	9,929
Cash Balance Plan \| Mutual funds-equity \| Level 1
Defined Benefit Plans
Assets at Fair Value	$ 11,744	$ 9,929