Defined Benefit Plans Plan Asset Allocation, Fair Value Hierarchy (Details) - USD ($) $ in Thousands		Dec. 31, 2016		Dec. 31, 2015
Investments [Domain]
Defined Benefit Plan, Fair Value of Plan Assets		$ 1,297,900		$ 1,337,405
Level One [Member] | Investments [Domain]
Defined Benefit Plan, Fair Value of Plan Assets		476,789		457,361
Level Two [Member] | Investments [Domain]
Defined Benefit Plan, Fair Value of Plan Assets		377,596		403,495
Measured at Net Asset Value [Member] | Investments [Domain]
Defined Benefit Plan, Fair Value of Plan Assets		443,515	[1]	476,549	[2]
United States Pension Plan of US Entity [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets		16,517
United States Pension Plan of US Entity [Member] | US Large Cap [Member]
Defined Benefit Plan, Fair Value of Plan Assets		97,530		100,226
United States Pension Plan of US Entity [Member] | US Small and Mid Cap [Member]
Defined Benefit Plan, Fair Value of Plan Assets		53,257		48,773
United States Pension Plan of US Entity [Member] | International Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		51,656		58,642
United States Pension Plan of US Entity [Member] | US Government and Corporate [Member]
Defined Benefit Plan, Fair Value of Plan Assets		123,663		143,787
United States Pension Plan of US Entity [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets		1,822	[3]	4,728	[4]
United States Pension Plan of US Entity [Member] | Level One [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets		16,517
United States Pension Plan of US Entity [Member] | Level One [Member] | US Small and Mid Cap [Member]
Defined Benefit Plan, Fair Value of Plan Assets		12,116		7,874
United States Pension Plan of US Entity [Member] | Level One [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets		1,822	[3]	1,811	[4]
United States Pension Plan of US Entity [Member] | Measured at Net Asset Value [Member] | US Large Cap [Member]
Defined Benefit Plan, Fair Value of Plan Assets		97,530	[1]	100,226	[2]
United States Pension Plan of US Entity [Member] | Measured at Net Asset Value [Member] | US Small and Mid Cap [Member]
Defined Benefit Plan, Fair Value of Plan Assets		41,141	[1]	40,899	[2]
United States Pension Plan of US Entity [Member] | Measured at Net Asset Value [Member] | International Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		51,656	[1]	58,642	[2]
United States Pension Plan of US Entity [Member] | Measured at Net Asset Value [Member] | US Government and Corporate [Member]
Defined Benefit Plan, Fair Value of Plan Assets		123,663	[1]	143,787	[2]
United States Pension Plan of US Entity [Member] | Measured at Net Asset Value [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets	[2],[4]			2,917
Foreign Pension Benefits [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets		8,758		12,832
Foreign Pension Benefits [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets		23,565	[3]	29,191	[4]
Foreign Pension Benefits [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		307,187		312,852
Foreign Pension Benefits [Member] | Non US Government Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets		613,945		626,374
Foreign Pension Benefits [Member] | Level One [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan, Fair Value of Plan Assets		8,758		12,832
Foreign Pension Benefits [Member] | Level One [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets		592	[3]	1,964	[4]
Foreign Pension Benefits [Member] | Level One [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		144,696		150,376
Foreign Pension Benefits [Member] | Level One [Member] | Non US Government Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets		292,288		282,504
Foreign Pension Benefits [Member] | Level Two [Member] | Other [Member]
Defined Benefit Plan, Fair Value of Plan Assets		22,973	[3]	27,227	[4]
Foreign Pension Benefits [Member] | Level Two [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		32,966		32,398
Foreign Pension Benefits [Member] | Level Two [Member] | Non US Government Bonds [Member]
Defined Benefit Plan, Fair Value of Plan Assets		321,657		343,870
Foreign Pension Benefits [Member] | Measured at Net Asset Value [Member] | Equity Securities [Member]
Defined Benefit Plan, Fair Value of Plan Assets		$ 129,525	[1]	$ 130,078	[2]

[1] Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient (the “NAV”) have not been classified in the fair value hierarchy. These investments, consisting of common/collective trusts, are valued using the NAV provided by the Trustee. The NAV is based on the underlying investments held by the fund, that are traded in an active market, less its liabilities. These investments are able to be redeemed in the near-term.

[2] Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient (the “NAV”) have not been classified in the fair value hierarchy. These investments, consisting primarily of common/collective trusts, are valued using the NAV provided by the Trustee. The NAV is based on the underlying investments held by the fund, that are traded in an active market, less its liabilities. These investments are able to be redeemed in the near-term.

[3] Represents diversified portfolio funds, real estate and reinsurance contracts and money market funds.

[4] Represents diversified portfolio funds, real estate and reinsurance contracts and money market funds.