Employee Benefit and Deferred Compensation Plans Employee Benefit Plans Stock Option Rollforward (Details) (USD $)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2013	Sep. 30, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding at beginning of period (shares)		1,060,350
Assumed from acquisition (shares)	11,557
Granted (shares)		0	52,500
Exercised (shares)		(183,082)
Forfeited (shares)		(1,899)
Options outstanding at end of period (shares)		875,369	1,060,350
Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Roll Forward]
Options outstanding at beginning of period (usd per share)		$ 18.64
Assumed from acquisition (usd per share)	$ 21.16
Granted (usd per share)		$ 0.00	$ 19.14
Exercised (usd per share)		$ 17.37
Forfeited (usd per share)		$ 20.77
Options outstanding at end of period (usd per share)		$ 18.90	$ 18.64

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

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- Definition

Weighted average price of options that were either forfeited or expired.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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Weighted average price at which grantees could acquire or could have acquired the underlying shares with respect to any other type of change in shares reserved for issuance.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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