Pension Plans - SERP (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
SERP
Defined contribution plan disclosures
Expense recorded	$ 22,000	$ 30,000	$ 46,000	$ 60,000
Employer contributions	0	0	99,000	126,000
Liability for SERP benefits	44,000		44,000		$ 97,000
401 (k) plan
Defined contribution plan disclosures
Expense recorded	$ 183,000	$ 198,000	$ 385,000	$ 428,000

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

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Details

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