Income Taxes - Reconciliation of Unrecognized Tax Benefits - (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Tax
Balance	$ 130,619	$ 127,085
Additions for current year tax positions	819	1,478
Additions for Reorganization Transactions	121,400
Reductions for prior years' tax positions: Expiration of statute of limitations	(140)	(254)
Reductions for prior years' tax positions: Other	(515)
Balance	130,783	128,309
Interest and Penalties
Balance	10,660	9,965
Additions for Reorganization Transactions	7,000	226
Additions for prior years' tax positions: Accrual of interest and penalties	509	209
Reductions for prior years' tax positions: Expiration of statute of limitations	(63)	(101)
Balance	11,106	10,299
Total
Balance	141,279	137,050
Additions for current year tax positions	819	1,478
Additions for Reorganization Transactions		226
Additions for prior years' tax positions: Accrual of interest and penalties	509	209
Reductions for prior years' tax positions: Expiration of statute of limitations	(203)	(355)
Reductions for prior years' tax positions: Other	(515)
Balance	141,889	138,608
Unrecognized tax benefits
Amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate	15,200	11,000
Unrecognized tax benefits attributable to tax refund claims in State of California	93,900
Unrecognized tax benefits, reasonably possible to decrease within the next 12 months	107,500
Unrecognized interest and penalties, reasonably possible to decrease within the next 12 months	5,600
Net expense attributable to interest and penalties recorded	100	$ 400
Accrued interest and penalties attributable to uncertain tax positions and undisputed tax adjustments	12,900		$ 12,800
Accrued interest and penalties attributable to unrecognized tax benefits	$ 11,100		$ 10,700