Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Transition adjustment for accounting standard adoption		$ 0
Operating right-of-use lease assets	$ 133,365		$ 0
Operating lease liability	$ 137,448
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating right-of-use lease assets		140,000
Operating lease liability		147,000
Tax Rate Reduction Related To Pension Liability | Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Transition adjustment for accounting standard adoption		700
Tax Effect Of Tax Reform On Items Remaining In AOCI, Currency Translation | Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Transition adjustment for accounting standard adoption		1,700
Distributions In Excess Of Earnings | Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Transition adjustment for accounting standard adoption		$ 1,000