Subsequent Events (Details) - Subsequent Event - Gibraltar Private Bank & Trust Company $ / shares in Units, shares in Thousands, $ in Millions	Oct. 19, 2017 USD ($) $ / shares shares
Subsequent Event [Line Items]
Number of shares issued for each share acquired	1.9749
Share price	$ 80.15
Equity issuable (in dollars per share)	$ 158.29
Equity issuable (shares) \| shares	2,790
Equity issuable \| $	$ 223

Business Acquisition, Conversion Rate of Stock Acquired

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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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