Acquisition - (PMFG) - Additional Information (Detail) - PMFG, Inc. [Member] - USD ($) $ / shares in Units, $ in Millions		3 Months Ended	6 Months Ended
	Sep. 03, 2015	Jun. 30, 2016	Jun. 30, 2016
Business Acquisition [Line Items]
Equity interests acquired	100.00%
Purchase price of acquisition	$ 136.7
Cash consideration per share	$ 6.85	$ 9.49	$ 9.49
Stock consideration per share	$ 6.85
Percentage of common stock converted into cash	44.50%
Value of shares transferred for cash	$ 64.6
Trading day period	15 days
Trading price	$ 9.6655
Exchange ratio	0.6456
Shares of common stock in aggregate stock consideration	7,602,166
Percentage of cash consideration			58.05%
Percentage of stock consideration			41.95%
Value of stock recorded for purchase accounting		$ 72.1	$ 72.1
Revenue from acquired entity		25.0	49.9
Income from acquired entity		$ 1.7	$ 4.9
Maximum [Member]
Business Acquisition [Line Items]
Common stock shares exchange ratio per share	0.6456
Minimum [Member]
Business Acquisition [Line Items]
Common stock shares exchange ratio per share	0.5282