Recently Issued and Adopted Accounting Pronouncements - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018	Jun. 30, 2018
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
ROU assets	$ 73,439		$ 0	$ 0
Short term lease liabilities	15,600
Long term lease liabilities	60,868		0	0
Cumulative decrease to retained earnings	$ 642,124		$ 787,356	$ 737,417
ASU 2016-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
ROU assets		$ 72,200
Short term lease liabilities		14,900
Long term lease liabilities		60,400
Cumulative decrease to retained earnings		$ (500)