Recently Issued Accounting Standards - Schedule of Changes in Earnings Per Share Basic and Diluted Effect of New Accounting Adoption (Detail) - $ / shares		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Basic EPS	[1]	$ 0.84	$ 0.43	$ 1.60	$ 1.02
Diluted EPS	[1]	0.83	$ 0.42	1.59	$ 1.01
Prior to Adoption of Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Basic EPS		0.83		1.54
Diluted EPS		0.82		1.53
Upon Adoption of Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Basic EPS		0.84		1.60
Diluted EPS		$ 0.83		$ 1.59

[1] The Company early adopted ASU 2016-09 on a prospective basis as required, related to the recognition of excess tax benefits to the income statement which were previously recorded in additional paid-in capital, effective January 1, 2016. This resulted in an additional 377,130 and 370,090 diluted weighted average number of common shares outstanding for the three and nine months ended September 30, 2016, respectively, and recognition of excess tax benefits of $1.8 million and $12.4 million in income tax provision for the three and nine months ended September 30, 2016, respectively. As a result, net earnings per common share increased by $0.01 per share and $0.06 per share for the three and nine months ended September 30, 2016, respectively. Refer to Note 2, “Recently Issued Accounting Standards” of the notes to the condensed consolidated financial statements for further details.