Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Accounting Pronouncements Accounting Pronouncements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 400		$ 3,300
Unrealized gain on equity securities	$ 24,497		24,497		$ (15,950)
Change in unrealized gains on equity securities, net of tax			$ 3,000
Earnings per share impact	$ 0.70	$ 0.74	$ 1.55	$ 1.38
Equity Securities [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unrealized gain on equity securities					$ 17,000
Earnings per share impact			$ 0.05