Stock-Based Compensation Plans (Stock Option Narrative) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock-based Compensation Plans Stock Option Narrative Details
Weighted-average grant-date fair value of options granted	$ 17.54	$ 5.66	$ 4.46
Total intrinsic value of stock options exercised	$ 31,500	$ 33,400	$ 2,000

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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

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Period Type:	duration