Income Taxes - Deferred Tax Assets and Liabilities Recognized in Company's Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Noncurrent deferred tax asset - Other noncurrent assets	$ 2,424	$ 1,852
Noncurrent deferred tax liabilities - Deferred income taxes	(163,863)	(146,574)
Total deferred tax (liabilities), net of valuation allowances	$ (161,439)	$ (144,722)

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31931-109318

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31917-109318

Name:	us-gaap_DeferredIncomeTaxAssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant