Summary of Significant Accounting Policies (Income Taxes) - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2016 USD ($)
Income Tax Contingency [Line Items]
Total amount of unrecognized tax benefits relating to uncertain tax positions	$ 57,900,000
Amount of unrecognized tax benefits change from year end relating to uncertain tax positions	3,400,000
Unrecognized tax benefits, increase resulting from current period tax positions	1,900,000
Unrecognized tax benefits, increase due to tax positions taken in prior period	1,900,000
Maximum [Member]
Income Tax Contingency [Line Items]
Reasonably possible reduction to the balance of unrecognized tax benefits in succeeding 12 months	$ 25,900,000
Tax Year 2010 [Member]
Income Tax Contingency [Line Items]
Income Tax Examination, Year under Examination	2010
Tax Year 2011 [Member]
Income Tax Contingency [Line Items]
Income Tax Examination, Year under Examination	2011
Tax Year 2012 [Member]
Income Tax Contingency [Line Items]
Income Tax Examination, Year under Examination	2012