Amount invested in funds

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- Definition

basis points earned on outstanding balance

+ References

No definition available.

+ Details

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- Definition

Fees paid to Union Bank as custodian

+ References

No definition available.

+ Details

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- Definition

Ownership Percentage, Related Party Ownership

+ References

No definition available.

+ Details

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- Definition

Percent of basis points earned on outstanding balance paid to custodian

+ References

No definition available.

+ Details

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- Definition

Percentage of basis points earned paid to Union Bank as custodian

+ References

No definition available.

+ Details

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- Definition

Receivables due from Union Bank and Trust

+ References

No definition available.

+ Details

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- Definition

Shares contributed to the trusts

+ References

No definition available.

+ Details

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- Definition

Revenue, comprised of base and incentive revenue derived from the management of joint ventures, managing third-party properties, or another entity's operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

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.

+ References

No definition available.

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Related Parties - Related Party Transactions Investment Services (Details) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) Basis_Point	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2011 shares
Union Bank and Whitetail Rock Capital Management management agreement dated May 9, 2011, effective as of May 1, 2011 [Member]
Related Party Transaction [Line Items]
Basis points Whitetail Rock Capital Management earns from Union Bank on outstanding balance \| Basis_Point	25
Amount invested in funds under Whitetail Rock Capital Management management agreement	$ 665,900
Percent of gains from the sale of securities Whitetail Rock Capital Management earns	50.00%
Fee revenue related to investment services	$ 9,200	$ 4,500	$ 2,700
Union Bank and Whitetail Rock Capital Management management agreement dated January 20, 2012 [Member]
Related Party Transaction [Line Items]
Basis points Whitetail Rock Capital Management earns from Union Bank on outstanding balance \| Basis_Point	5
Fee revenue related to investment services	$ 161	142	$ 71
Receivables due from Union Bank and Trust	$ 200	$ 800
Union Bank and Whitetail Rock Capital Management management agreement dated January 20, 2012 [Member] \| Board of Directors Chairman [Member]
Related Party Transaction [Line Items]
Shares contributed to the trusts (in shares) \| shares			3,000	3,375
Union Bank and Whitetail Rock Capital Management management agreement dated January 20, 2012 [Member] \| Director [Member]
Related Party Transaction [Line Items]
Shares contributed to the trusts (in shares) \| shares		1,200
SLABS Fund-I, SLABS Fund-II, SLABS Fund-III, SLABS Fund-IV, and SLABS Fund-V [Member]
Related Party Transaction [Line Items]
Basis points Whitetail Rock Capital Management earns from Union Bank on outstanding balance	50
Amount invested in funds under Whitetail Rock Capital Management management agreement	$ 149,400
Percentage of basis points earned paid to Union Bank as custodian	50.00%
Fees paid to Union Bank as custodian	$ 300	$ 400	$ 400
Union Financial Services [Member] \| Mr. Butterfield [Member]
Related Party Transaction [Line Items]
Ownership percentage, related party	50.00%
Union Financial Services [Member] \| Mr. Dunlap [Member]
Related Party Transaction [Line Items]
Ownership percentage, related party	50.00%